refactor CUC again

CHANGELOG.md

@@ -8,8 +8,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 # [unreleased]
 
-# [v0.11.0-rc.1] 2024-04-03
-
 Major API changes for the time API. If you are using the time API, it is strongly recommended
 to check all the API changes in the **Changed** chapter.
 
@@ -26,14 +24,9 @@ to check all the API changes in the **Changed** chapter.
 - Added basic support conversions to the `time` library. Introduce new `chrono` and `timelib`
   feature gate.
 - Added `CcsdsTimeProvider::timelib_date_time`.
-- Optional support for `defmt` by adding optional `defmt::Format` derives for common types.
 
 ## Changed
 
-- `PusTcCreator::new_simple` now expects a valid slice for the source data instead of an optional
-  slice. For telecommands without application data, `&[]` can be passed.
-- `PusTmSecondaryHeader` constructors now expects a valid slice for the time stamp instead of an
-  optional slice.
 - Renamed `CcsdsTimeProvider::date_time` to `CcsdsTimeProvider::chrono_date_time`
 - Renamed `CcsdsTimeCodes` to `CcsdsTimeCode`
 - Renamed `cds::TimeProvider` to `cds::CdsTime`
@@ -41,7 +34,6 @@ to check all the API changes in the **Changed** chapter.
 - `UnixTimestamp` renamed to `UnixTime`
 - `UnixTime` seconds are now private and can be retrieved using the `secs` member method.
 - `UnixTime::new` renamed to `UnixTime::new_checked`.
-- `UnixTime::secs` renamed to `UnixTime::as_secs`.
 - `UnixTime` now has a nanosecond subsecond precision. The `new` constructor now expects
    nanoseconds as the second argument.
 - Added new `UnixTime::new_subsec_millis` and `UnixTime::new_subsec_millis_checked` API
@@ -51,16 +43,6 @@ to check all the API changes in the **Changed** chapter.
 - `CcsdsTimeProvider::date_time` renamed to `CcsdsTimeProvider::chrono_date_time`.
 - Added `UnixTime::MIN`, `UnixTime::MAX` and `UnixTime::EPOCH`.
 - Added `UnixTime::timelib_date_time`.
-- Error handling for ECSS and time module is more granular now, with a new
-  `DateBeforeCcsdsEpochError` error and a `DateBeforeCcsdsEpoch` enum variant for both
-  `CdsError` and `CucError`.
-- `PusTmCreator` now has two lifetimes: One for the raw source data buffer and one for the
-  raw timestamp.
-- Time API `from_now*` API renamed to `now*`.
-
-## Removed
-
-- Legacy `PusTm` and `PusTc` objects.
 
 # [v0.11.0-rc.0] 2024-03-04
 

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "spacepackets"
-version = "0.11.0-rc.1"
+version = "0.11.0-rc.0"
 edition = "2021"
 rust-version = "1.61"
 authors = ["Robin Mueller <muellerr@irs.uni-stuttgart.de>"]
@@ -48,10 +48,6 @@ optional = true
 version = "0.2"
 default-features = false
 
-[dependencies.defmt]
-version = "0.3"
-optional = true
-
 [dev-dependencies]
 postcard = "1"
 chrono = "0.4"
@@ -63,8 +59,7 @@ serde = ["dep:serde", "chrono/serde"]
 alloc = ["postcard/alloc", "chrono/alloc"]
 chrono = ["dep:chrono"]
 timelib = ["dep:time"]
-defmt = ["dep:defmt"]
 
 [package.metadata.docs.rs]
 all-features = true
-rustdoc-args = ["--cfg", "docs_rs", "--generate-link-to-definition"]
+rustdoc-args = ["--cfg", "doc_cfg", "--generate-link-to-definition"]

README.md

@@ -45,8 +45,6 @@ deserializing them with an appropriate `serde` provider like
  - [`serde`](https://serde.rs/): Adds `serde` support for most types by adding `Serialize` and `Deserialize` `derive`s
  - [`chrono`](https://crates.io/crates/chrono): Add basic support for the `chrono` time library.
  - [`timelib`](https://crates.io/crates/time): Add basic support for the `time` time library.
- - [`defmt`](https://defmt.ferrous-systems.com/): Add support for the `defmt` by adding the
-   [`defmt::Format`](https://defmt.ferrous-systems.com/format) derive on many types.
 
 # Examples
 

release-checklist.md

@@ -4,11 +4,11 @@ Checklist for new releases
 # Pre-Release
 
 1. Make sure any new modules are documented sufficiently enough and check docs with
-   `cargo +nightly doc --all-features --config 'build.rustdocflags=["--cfg", "docs_rs"]' --open`.
+   `cargo +nightly doc --all-features --config 'rustdocflags=["--cfg", "doc_cfg"]' --open`.
 2. Bump version specifier in `Cargo.toml`.
 3. Update `CHANGELOG.md`: Convert `unreleased` section into version section with date and add new
    `unreleased` section.
-4. Run `cargo test --all-features` or `cargo nextest r --all-features`.
+4. Run `cargo test --all-features`.
 5. Run `cargo fmt` and `cargo clippy`. Check `cargo msrv` against MSRV in `Cargo.toml`.
 6. Wait for CI/CD results for EGit and Github. These also check cross-compilation for bare-metal
    targets.

src/cfdp/lv.rs

@@ -20,7 +20,6 @@ pub const MIN_LV_LEN: usize = 1;
 ///    this will be the lifetime of that data reference.
 #[derive(Debug, Copy, Clone, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct Lv<'data> {
     data: &'data [u8],
     // If the LV was generated from a raw bytestream, this will contain the start of the
@@ -89,6 +88,7 @@ impl<'data> Lv<'data> {
     /// Helper function to build a string LV. This is especially useful for the file or directory
     /// path LVs
     #[cfg(feature = "std")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
     pub fn new_from_string(string: &'data String) -> Result<Lv<'data>, TlvLvError> {
         Self::new(string.as_bytes())
     }

src/cfdp/mod.rs

@@ -18,7 +18,6 @@ pub const CFDP_VERSION_2: u8 = 0b001;
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum PduType {
     FileDirective = 0,
@@ -27,7 +26,6 @@ pub enum PduType {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum Direction {
     TowardsReceiver = 0,
@@ -36,7 +34,6 @@ pub enum Direction {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum TransmissionMode {
     Acknowledged = 0,
@@ -45,7 +42,6 @@ pub enum TransmissionMode {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum CrcFlag {
     NoCrc = 0,
@@ -73,7 +69,6 @@ impl From<CrcFlag> for bool {
 /// Always 0 and ignored for File Directive PDUs (CCSDS 727.0-B-5 P.75)
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum SegmentMetadataFlag {
     NotPresent = 0,
@@ -83,7 +78,6 @@ pub enum SegmentMetadataFlag {
 /// Always 0 and ignored for File Directive PDUs (CCSDS 727.0-B-5 P.75)
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum SegmentationControl {
     NoRecordBoundaryPreservation = 0,
@@ -92,7 +86,6 @@ pub enum SegmentationControl {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum FaultHandlerCode {
     NoticeOfCancellation = 0b0001,
@@ -103,7 +96,6 @@ pub enum FaultHandlerCode {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum ConditionCode {
     /// This is not an error condition for which a faulty handler override can be specified
@@ -126,7 +118,6 @@ pub enum ConditionCode {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum LargeFileFlag {
     /// 32 bit maximum file size and FSS size
@@ -138,7 +129,6 @@ pub enum LargeFileFlag {
 /// Transaction status for the ACK PDU field according to chapter 5.2.4 of the CFDP standard.
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum TransactionStatus {
     /// Transaction is not currently active and the CFDP implementation does not retain a
@@ -156,7 +146,6 @@ pub enum TransactionStatus {
 /// [SANA Checksum Types registry](https://sanaregistry.org/r/checksum_identifiers/)
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum ChecksumType {
     /// Modular legacy checksum
@@ -178,7 +167,6 @@ pub const NULL_CHECKSUM_U32: [u8; 4] = [0; 4];
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum TlvLvError {
     DataTooLarge(usize),
     ByteConversion(ByteConversionError),

src/cfdp/pdu/ack.rs

@@ -15,7 +15,6 @@ use serde::{Deserialize, Serialize};
 /// For more information, refer to CFDP chapter 5.2.4.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct AckPdu {
     pdu_header: PduHeader,
     directive_code_of_acked_pdu: FileDirectiveType,

src/cfdp/pdu/eof.rs

@@ -15,7 +15,6 @@ use super::{CfdpPdu, WritablePduPacket};
 /// For more information, refer to CFDP chapter 5.2.2.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct EofPdu {
     pdu_header: PduHeader,
     condition_code: ConditionCode,

src/cfdp/pdu/finished.rs

@@ -14,7 +14,6 @@ use super::{CfdpPdu, WritablePduPacket};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum DeliveryCode {
     Complete = 0,
@@ -23,7 +22,6 @@ pub enum DeliveryCode {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum FileStatus {
     DiscardDeliberately = 0b00,
@@ -36,7 +34,6 @@ pub enum FileStatus {
 ///
 /// For more information, refer to CFDP chapter 5.2.3.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct FinishedPduCreator<'fs_responses> {
     pdu_header: PduHeader,
     condition_code: ConditionCode,
@@ -222,7 +219,6 @@ impl<'buf> Iterator for FilestoreResponseIterator<'buf> {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct FinishedPduReader<'buf> {
     pdu_header: PduHeader,
     condition_code: ConditionCode,

src/cfdp/pdu/metadata.rs

@@ -15,7 +15,6 @@ use super::{CfdpPdu, WritablePduPacket};
 
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct MetadataGenericParams {
     pub closure_requested: bool,
     pub checksum_type: ChecksumType,
@@ -56,7 +55,6 @@ pub fn build_metadata_opts_from_vec(
 /// This abstraction exposes a specialized API for creating metadata PDUs as specified in
 /// CFDP chapter 5.2.5.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct MetadataPduCreator<'src_name, 'dest_name, 'opts> {
     pdu_header: PduHeader,
     metadata_params: MetadataGenericParams,
@@ -243,7 +241,6 @@ impl<'opts> Iterator for OptionsIter<'opts> {
 /// involved.
 #[derive(Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct MetadataPduReader<'buf> {
     pdu_header: PduHeader,
     metadata_params: MetadataGenericParams,

src/cfdp/pdu/mod.rs

@@ -18,7 +18,6 @@ pub mod nak;
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum FileDirectiveType {
     EofPdu = 0x04,
@@ -221,7 +220,6 @@ pub trait CfdpPdu {
 /// same.
 #[derive(Debug, Copy, Clone, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct CommonPduConfig {
     source_entity_id: UnsignedByteField,
     dest_entity_id: UnsignedByteField,
@@ -360,7 +358,6 @@ pub const FIXED_HEADER_LEN: usize = 4;
 /// For detailed information, refer to chapter 5.1 of the CFDP standard.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PduHeader {
     pdu_type: PduType,
     pdu_conf: CommonPduConfig,

src/cfdp/pdu/nak.rs

@@ -12,7 +12,6 @@ use super::{
 /// Helper type to encapsulate both normal file size segment requests and large file size segment
 /// requests.
 #[derive(Debug, PartialEq, Eq, Clone)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum SegmentRequests<'a> {
     U32Pairs(&'a [(u32, u32)]),
     U64Pairs(&'a [(u64, u64)]),
@@ -32,7 +31,6 @@ impl SegmentRequests<'_> {
 /// It exposes a specialized API which simplifies to generate these NAK PDUs with the
 /// format according to CFDP chapter 5.2.6.
 #[derive(Debug, Clone, PartialEq, Eq)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct NakPduCreator<'seg_reqs> {
     pdu_header: PduHeader,
     start_of_scope: u64,
@@ -355,7 +353,6 @@ impl<T: SegReqFromBytes> SegmentRequestIter<'_, T> {
 ///
 /// The NAK format is expected to be conforming to CFDP chapter 5.2.6.
 #[derive(Debug, PartialEq, Eq)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct NakPduReader<'seg_reqs> {
     pdu_header: PduHeader,
     start_of_scope: u64,

src/cfdp/tlv/mod.rs

@@ -52,7 +52,6 @@ pub trait WritableTlv {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum TlvType {
     FilestoreRequest = 0x00,
@@ -65,7 +64,6 @@ pub enum TlvType {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum TlvTypeField {
     Standard(TlvType),
     Custom(u8),
@@ -73,7 +71,6 @@ pub enum TlvTypeField {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum FilestoreActionCode {
     CreateFile = 0b0000,
@@ -121,7 +118,6 @@ impl From<TlvTypeField> for u8 {
 ///    this will be the lifetime of that data reference.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct Tlv<'data> {
     tlv_type_field: TlvTypeField,
     #[cfg_attr(feature = "serde", serde(borrow))]
@@ -228,7 +224,6 @@ pub(crate) fn verify_tlv_type(raw_type: u8, expected_tlv_type: TlvType) -> Resul
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct EntityIdTlv {
     entity_id: UnsignedByteField,
 }
@@ -353,7 +348,6 @@ pub fn fs_request_has_second_filename(action_code: FilestoreActionCode) -> bool
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 struct FilestoreTlvBase<'first_name, 'second_name> {
     pub action_code: FilestoreActionCode,
     #[cfg_attr(feature = "serde", serde(borrow))]
@@ -567,7 +561,6 @@ impl GenericTlv for FilestoreRequestTlv<'_, '_> {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct FilestoreResponseTlv<'first_name, 'second_name, 'fs_msg> {
     #[cfg_attr(feature = "serde", serde(borrow))]
     base: FilestoreTlvBase<'first_name, 'second_name>,

src/ecss/hk.rs

@@ -5,7 +5,6 @@ use serde::{Deserialize, Serialize};
 
 #[derive(Debug, Eq, PartialEq, Copy, Clone, IntoPrimitive, TryFromPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 pub enum Subservice {
     // Regular HK

src/ecss/mod.rs

@@ -74,7 +74,6 @@ pub enum PusServiceId {
 /// All PUS versions. Only PUS C is supported by this library.
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
 pub enum PusVersion {
     EsaPus = 0,
@@ -151,7 +150,6 @@ pub enum PfcReal {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum PusError {
     VersionNotSupported(PusVersion),
     ChecksumFailure(u16),
@@ -207,12 +205,13 @@ pub trait PusPacket: CcsdsPacket {
     fn crc16(&self) -> Option<u16>;
 }
 
-pub(crate) fn crc_from_raw_data(raw_data: &[u8]) -> Result<u16, ByteConversionError> {
+pub(crate) fn crc_from_raw_data(raw_data: &[u8]) -> Result<u16, PusError> {
     if raw_data.len() < 2 {
         return Err(ByteConversionError::FromSliceTooSmall {
             found: raw_data.len(),
             expected: 2,
-        });
+        }
+        .into());
     }
     Ok(u16::from_be_bytes(
         raw_data[raw_data.len() - 2..raw_data.len()]
@@ -227,16 +226,35 @@ pub(crate) fn calc_pus_crc16(bytes: &[u8]) -> u16 {
     digest.finalize()
 }
 
+pub(crate) fn crc_procedure(
+    calc_on_serialization: bool,
+    cached_crc16: &Option<u16>,
+    start_idx: usize,
+    curr_idx: usize,
+    slice: &[u8],
+) -> Result<u16, PusError> {
+    let crc16;
+    if calc_on_serialization {
+        crc16 = calc_pus_crc16(&slice[start_idx..curr_idx])
+    } else if cached_crc16.is_none() {
+        return Err(PusError::CrcCalculationMissing);
+    } else {
+        crc16 = cached_crc16.unwrap();
+    }
+    Ok(crc16)
+}
+
 pub(crate) fn user_data_from_raw(
     current_idx: usize,
     total_len: usize,
     slice: &[u8],
-) -> Result<&[u8], ByteConversionError> {
+) -> Result<&[u8], PusError> {
     match current_idx {
         _ if current_idx > total_len - 2 => Err(ByteConversionError::FromSliceTooSmall {
             found: total_len - 2,
             expected: current_idx,
-        }),
+        }
+        .into()),
         _ => Ok(&slice[current_idx..total_len - 2]),
     }
 }

src/ecss/tc.rs

@@ -48,6 +48,8 @@ use zerocopy::AsBytes;
 #[cfg(feature = "alloc")]
 use alloc::vec::Vec;
 
+pub use legacy_tc::*;
+
 /// PUS C secondary header length is fixed
 pub const PUC_TC_SECONDARY_HEADER_LEN: usize = size_of::<zc::PusTcSecondaryHeader>();
 pub const PUS_TC_MIN_LEN_WITHOUT_APP_DATA: usize =
@@ -59,7 +61,6 @@ pub trait IsPusTelecommand {}
 
 #[derive(Debug, Eq, PartialEq, Copy, Clone, IntoPrimitive, TryFromPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[repr(u8)]
 enum AckOpts {
     Acceptance = 0b1000,
@@ -145,7 +146,6 @@ pub mod zc {
 
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PusTcSecondaryHeader {
     pub service: u8,
     pub subservice: u8,
@@ -212,6 +212,333 @@ impl PusTcSecondaryHeader {
     }
 }
 
+pub mod legacy_tc {
+    use crate::ecss::tc::{
+        zc, GenericPusTcSecondaryHeader, IsPusTelecommand, PusTcSecondaryHeader, ACK_ALL,
+        PUC_TC_SECONDARY_HEADER_LEN, PUS_TC_MIN_LEN_WITHOUT_APP_DATA,
+    };
+    use crate::ecss::{
+        ccsds_impl, crc_from_raw_data, crc_procedure, sp_header_impls,
+        verify_crc16_ccitt_false_from_raw_to_pus_error, PusError, PusPacket, WritablePusPacket,
+        CCSDS_HEADER_LEN,
+    };
+    use crate::ecss::{user_data_from_raw, PusVersion};
+    use crate::SequenceFlags;
+    use crate::{ByteConversionError, CcsdsPacket, PacketType, SpHeader, CRC_CCITT_FALSE};
+    use core::mem::size_of;
+    use delegate::delegate;
+    use zerocopy::AsBytes;
+
+    #[cfg(feature = "alloc")]
+    use alloc::vec::Vec;
+
+    #[cfg(feature = "serde")]
+    use serde::{Deserialize, Serialize};
+
+    /// This class models the PUS C telecommand packet. It is the primary data structure to generate the
+    /// raw byte representation of a PUS telecommand or to deserialize from one from raw bytes.
+    ///
+    /// This class also derives the [serde::Serialize] and [serde::Deserialize] trait if the
+    /// [serde] feature is used, which allows to send around TC packets in a raw byte format using a
+    /// serde provider like [postcard](https://docs.rs/postcard/latest/postcard/).
+    ///
+    /// There is no spare bytes support yet.
+    ///
+    /// # Lifetimes
+    ///
+    /// * `'raw_data` - If the TC is not constructed from a raw slice, this will be the life time of
+    ///    a buffer where the user provided application data will be serialized into. If it
+    ///    is, this is the lifetime of the raw byte slice it is constructed from.
+    #[derive(Eq, Copy, Clone, Debug)]
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+    pub struct PusTc<'raw_data> {
+        sp_header: SpHeader,
+        pub sec_header: PusTcSecondaryHeader,
+        /// If this is set to false, a manual call to [PusTc::calc_own_crc16] or
+        /// [PusTc::update_packet_fields] is necessary for the serialized or cached CRC16 to be valid.
+        pub calc_crc_on_serialization: bool,
+        #[cfg_attr(feature = "serde", serde(skip))]
+        raw_data: Option<&'raw_data [u8]>,
+        app_data: &'raw_data [u8],
+        crc16: Option<u16>,
+    }
+
+    impl<'raw_data> PusTc<'raw_data> {
+        /// Generates a new struct instance.
+        ///
+        /// # Arguments
+        ///
+        /// * `sp_header` - Space packet header information. The correct packet type will be set
+        ///     automatically
+        /// * `sec_header` - Information contained in the data field header, including the service
+        ///     and subservice type
+        /// * `app_data` - Custom application data
+        /// * `set_ccsds_len` - Can be used to automatically update the CCSDS space packet data length
+        ///     field. If this is not set to true, [PusTc::update_ccsds_data_len] can be called to set
+        ///     the correct value to this field manually
+        #[deprecated(
+            since = "0.7.0",
+            note = "Use specialized PusTcCreator or PusTcReader classes instead"
+        )]
+        pub fn new(
+            sp_header: &mut SpHeader,
+            sec_header: PusTcSecondaryHeader,
+            app_data: Option<&'raw_data [u8]>,
+            set_ccsds_len: bool,
+        ) -> Self {
+            sp_header.set_packet_type(PacketType::Tc);
+            sp_header.set_sec_header_flag();
+            let mut pus_tc = Self {
+                sp_header: *sp_header,
+                raw_data: None,
+                app_data: app_data.unwrap_or(&[]),
+                sec_header,
+                calc_crc_on_serialization: true,
+                crc16: None,
+            };
+            if set_ccsds_len {
+                pus_tc.update_ccsds_data_len();
+            }
+            pus_tc
+        }
+
+        /// Simplified version of the [PusTc::new] function which allows to only specify service and
+        /// subservice instead of the full PUS TC secondary header.
+        #[deprecated(
+            since = "0.7.0",
+            note = "Use specialized PusTcCreator or PusTcReader classes instead"
+        )]
+        pub fn new_simple(
+            sph: &mut SpHeader,
+            service: u8,
+            subservice: u8,
+            app_data: Option<&'raw_data [u8]>,
+            set_ccsds_len: bool,
+        ) -> Self {
+            #[allow(deprecated)]
+            Self::new(
+                sph,
+                PusTcSecondaryHeader::new(service, subservice, ACK_ALL, 0),
+                app_data,
+                set_ccsds_len,
+            )
+        }
+
+        pub fn sp_header(&self) -> &SpHeader {
+            &self.sp_header
+        }
+
+        pub fn set_ack_field(&mut self, ack: u8) -> bool {
+            if ack > 0b1111 {
+                return false;
+            }
+            self.sec_header.ack = ack & 0b1111;
+            true
+        }
+
+        pub fn set_source_id(&mut self, source_id: u16) {
+            self.sec_header.source_id = source_id;
+        }
+
+        sp_header_impls!();
+
+        /// Calculate the CCSDS space packet data length field and sets it
+        /// This is called automatically if the `set_ccsds_len` argument in the [PusTc::new] call was
+        /// used.
+        /// If this was not done or the application data is set or changed after construction,
+        /// this function needs to be called to ensure that the data length field of the CCSDS header
+        /// is set correctly.
+        pub fn update_ccsds_data_len(&mut self) {
+            self.sp_header.data_len =
+                self.len_written() as u16 - size_of::<crate::zc::SpHeader>() as u16 - 1;
+        }
+
+        /// This function should be called before the TC packet is serialized if
+        /// [PusTc::calc_crc_on_serialization] is set to False. It will calculate and cache the CRC16.
+        pub fn calc_own_crc16(&mut self) {
+            let mut digest = CRC_CCITT_FALSE.digest();
+            let sph_zc = crate::zc::SpHeader::from(self.sp_header);
+            digest.update(sph_zc.as_bytes());
+            let pus_tc_header = zc::PusTcSecondaryHeader::try_from(self.sec_header).unwrap();
+            digest.update(pus_tc_header.as_bytes());
+            if !self.app_data.is_empty() {
+                digest.update(self.app_data);
+            }
+            self.crc16 = Some(digest.finalize())
+        }
+
+        /// This helper function calls both [PusTc::update_ccsds_data_len] and [PusTc::calc_own_crc16].
+        pub fn update_packet_fields(&mut self) {
+            self.update_ccsds_data_len();
+            self.calc_own_crc16();
+        }
+
+        #[cfg(feature = "alloc")]
+        #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
+        pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> Result<usize, PusError> {
+            let sph_zc = crate::zc::SpHeader::from(self.sp_header);
+            let appended_len = PUS_TC_MIN_LEN_WITHOUT_APP_DATA + self.app_data.len();
+            let start_idx = vec.len();
+            let mut ser_len = 0;
+            vec.extend_from_slice(sph_zc.as_bytes());
+            ser_len += sph_zc.as_bytes().len();
+            // The PUS version is hardcoded to PUS C
+            let pus_tc_header = zc::PusTcSecondaryHeader::try_from(self.sec_header).unwrap();
+            vec.extend_from_slice(pus_tc_header.as_bytes());
+            ser_len += pus_tc_header.as_bytes().len();
+            vec.extend_from_slice(self.app_data);
+            ser_len += self.app_data.len();
+            let crc16 = crc_procedure(
+                self.calc_crc_on_serialization,
+                &self.crc16,
+                start_idx,
+                ser_len,
+                &vec[start_idx..ser_len],
+            )?;
+            vec.extend_from_slice(crc16.to_be_bytes().as_slice());
+            Ok(appended_len)
+        }
+
+        /// Create a [PusTc] instance from a raw slice. On success, it returns a tuple containing
+        /// the instance and the found byte length of the packet.
+        #[deprecated(
+            since = "0.7.0",
+            note = "Use specialized PusTcCreator or PusTcReader classes instead"
+        )]
+        pub fn from_bytes(slice: &'raw_data [u8]) -> Result<(Self, usize), PusError> {
+            let raw_data_len = slice.len();
+            if raw_data_len < PUS_TC_MIN_LEN_WITHOUT_APP_DATA {
+                return Err(ByteConversionError::FromSliceTooSmall {
+                    found: raw_data_len,
+                    expected: PUS_TC_MIN_LEN_WITHOUT_APP_DATA,
+                }
+                .into());
+            }
+            let mut current_idx = 0;
+            let (sp_header, _) = SpHeader::from_be_bytes(&slice[0..CCSDS_HEADER_LEN])?;
+            current_idx += CCSDS_HEADER_LEN;
+            let total_len = sp_header.total_len();
+            if raw_data_len < total_len || total_len < PUS_TC_MIN_LEN_WITHOUT_APP_DATA {
+                return Err(ByteConversionError::FromSliceTooSmall {
+                    found: raw_data_len,
+                    expected: total_len,
+                }
+                .into());
+            }
+            let sec_header = zc::PusTcSecondaryHeader::from_bytes(
+                &slice[current_idx..current_idx + PUC_TC_SECONDARY_HEADER_LEN],
+            )
+            .ok_or(ByteConversionError::ZeroCopyFromError)?;
+            current_idx += PUC_TC_SECONDARY_HEADER_LEN;
+            let raw_data = &slice[0..total_len];
+            let pus_tc = Self {
+                sp_header,
+                sec_header: PusTcSecondaryHeader::try_from(sec_header).unwrap(),
+                raw_data: Some(raw_data),
+                app_data: user_data_from_raw(current_idx, total_len, slice)?,
+                calc_crc_on_serialization: false,
+                crc16: Some(crc_from_raw_data(raw_data)?),
+            };
+            verify_crc16_ccitt_false_from_raw_to_pus_error(
+                raw_data,
+                pus_tc.crc16.expect("CRC16 invalid"),
+            )?;
+            Ok((pus_tc, total_len))
+        }
+
+        #[deprecated(since = "0.5.2", note = "use raw_bytes() instead")]
+        pub fn raw(&self) -> Option<&'raw_data [u8]> {
+            self.raw_bytes()
+        }
+
+        /// If [Self] was constructed [Self::from_bytes], this function will return the slice it was
+        /// constructed from. Otherwise, [None] will be returned.
+        pub fn raw_bytes(&self) -> Option<&'raw_data [u8]> {
+            self.raw_data
+        }
+    }
+
+    impl WritablePusPacket for PusTc<'_> {
+        fn len_written(&self) -> usize {
+            PUS_TC_MIN_LEN_WITHOUT_APP_DATA + self.app_data.len()
+        }
+
+        /// Write the raw PUS byte representation to a provided buffer.
+        fn write_to_bytes(&self, slice: &mut [u8]) -> Result<usize, PusError> {
+            let mut curr_idx = 0;
+            let tc_header_len = size_of::<zc::PusTcSecondaryHeader>();
+            let total_size = self.len_written();
+            if total_size > slice.len() {
+                return Err(ByteConversionError::ToSliceTooSmall {
+                    found: slice.len(),
+                    expected: total_size,
+                }
+                .into());
+            }
+            self.sp_header.write_to_be_bytes(slice)?;
+            curr_idx += CCSDS_HEADER_LEN;
+            let sec_header = zc::PusTcSecondaryHeader::try_from(self.sec_header).unwrap();
+            sec_header
+                .write_to_bytes(&mut slice[curr_idx..curr_idx + tc_header_len])
+                .ok_or(ByteConversionError::ZeroCopyToError)?;
+
+            curr_idx += tc_header_len;
+            slice[curr_idx..curr_idx + self.app_data.len()].copy_from_slice(self.app_data);
+            curr_idx += self.app_data.len();
+            let crc16 = crc_procedure(
+                self.calc_crc_on_serialization,
+                &self.crc16,
+                0,
+                curr_idx,
+                slice,
+            )?;
+            slice[curr_idx..curr_idx + 2].copy_from_slice(crc16.to_be_bytes().as_slice());
+            curr_idx += 2;
+            Ok(curr_idx)
+        }
+    }
+
+    impl PartialEq for PusTc<'_> {
+        fn eq(&self, other: &Self) -> bool {
+            self.sp_header == other.sp_header
+                && self.sec_header == other.sec_header
+                && self.app_data == other.app_data
+        }
+    }
+
+    impl CcsdsPacket for PusTc<'_> {
+        ccsds_impl!();
+    }
+
+    impl PusPacket for PusTc<'_> {
+        delegate!(to self.sec_header {
+            fn pus_version(&self) -> PusVersion;
+            fn service(&self) -> u8;
+            fn subservice(&self) -> u8;
+        });
+
+        fn user_data(&self) -> &[u8] {
+            self.app_data
+        }
+
+        fn crc16(&self) -> Option<u16> {
+            self.crc16
+        }
+    }
+
+    impl GenericPusTcSecondaryHeader for PusTc<'_> {
+        delegate!(to self.sec_header {
+            fn pus_version(&self) -> PusVersion;
+            fn service(&self) -> u8;
+            fn subservice(&self) -> u8;
+            fn source_id(&self) -> u16;
+            fn ack_flags(&self) -> u8;
+        });
+    }
+
+    impl IsPusTelecommand for PusTc<'_> {}
+}
+
 /// This class can be used to create PUS C telecommand packet. It is the primary data structure to
 /// generate the raw byte representation of a PUS telecommand.
 ///
@@ -222,7 +549,6 @@ impl PusTcSecondaryHeader {
 /// There is no spare bytes support yet.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PusTcCreator<'raw_data> {
     sp_header: SpHeader,
     pub sec_header: PusTcSecondaryHeader,
@@ -240,7 +566,7 @@ impl<'raw_data> PusTcCreator<'raw_data> {
     ///     and subservice type
     /// * `app_data` - Custom application data
     /// * `set_ccsds_len` - Can be used to automatically update the CCSDS space packet data length
-    ///     field. If this is not set to true, [Self::update_ccsds_data_len] can be called to set
+    ///     field. If this is not set to true, [PusTc::update_ccsds_data_len] can be called to set
     ///     the correct value to this field manually
     pub fn new(
         sp_header: &mut SpHeader,
@@ -261,19 +587,19 @@ impl<'raw_data> PusTcCreator<'raw_data> {
         pus_tc
     }
 
-    /// Simplified version of the [Self::new] function which allows to only specify service
+    /// Simplified version of the [PusTcCreator::new] function which allows to only specify service
     /// and subservice instead of the full PUS TC secondary header.
     pub fn new_simple(
         sph: &mut SpHeader,
         service: u8,
         subservice: u8,
-        app_data: &'raw_data [u8],
+        app_data: Option<&'raw_data [u8]>,
         set_ccsds_len: bool,
     ) -> Self {
         Self::new(
             sph,
             PusTcSecondaryHeader::new(service, subservice, ACK_ALL, 0),
-            app_data,
+            app_data.unwrap_or(&[]),
             set_ccsds_len,
         )
     }
@@ -305,7 +631,7 @@ impl<'raw_data> PusTcCreator<'raw_data> {
     sp_header_impls!();
 
     /// Calculate the CCSDS space packet data length field and sets it
-    /// This is called automatically if the `set_ccsds_len` argument in the [Self::new] call was
+    /// This is called automatically if the `set_ccsds_len` argument in the [PusTc::new] call was
     /// used.
     /// If this was not done or the application data is set or changed after construction,
     /// this function needs to be called to ensure that the data length field of the CCSDS header
@@ -315,7 +641,8 @@ impl<'raw_data> PusTcCreator<'raw_data> {
             self.len_written() as u16 - size_of::<crate::zc::SpHeader>() as u16 - 1;
     }
 
-    /// This function calculates and returns the CRC16 for the current packet.
+    /// This function should be called before the TC packet is serialized if
+    /// [PusTc::calc_crc_on_serialization] is set to False. It will calculate and cache the CRC16.
     pub fn calc_own_crc16(&self) -> u16 {
         let mut digest = CRC_CCITT_FALSE.digest();
         let sph_zc = crate::zc::SpHeader::from(self.sp_header);
@@ -327,7 +654,8 @@ impl<'raw_data> PusTcCreator<'raw_data> {
     }
 
     #[cfg(feature = "alloc")]
-    pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> usize {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
+    pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> Result<usize, PusError> {
         let sph_zc = crate::zc::SpHeader::from(self.sp_header);
         let mut appended_len = PUS_TC_MIN_LEN_WITHOUT_APP_DATA;
         appended_len += self.app_data.len();
@@ -340,7 +668,7 @@ impl<'raw_data> PusTcCreator<'raw_data> {
         let mut digest = CRC_CCITT_FALSE.digest();
         digest.update(&vec[start_idx..start_idx + appended_len - 2]);
         vec.extend_from_slice(&digest.finalize().to_be_bytes());
-        appended_len
+        Ok(appended_len)
     }
 }
 
@@ -424,7 +752,6 @@ impl IsPusTelecommand for PusTcCreator<'_> {}
 /// * `'raw_data` - Lifetime of the provided raw slice.
 #[derive(Eq, Copy, Clone, Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PusTcReader<'raw_data> {
     #[cfg_attr(feature = "serde", serde(skip))]
     raw_data: &'raw_data [u8],
@@ -436,8 +763,7 @@ pub struct PusTcReader<'raw_data> {
 
 impl<'raw_data> PusTcReader<'raw_data> {
     /// Create a [PusTcReader] instance from a raw slice. On success, it returns a tuple containing
-    /// the instance and the found byte length of the packet. This function also performs a CRC
+    /// the instance and the found byte length of the packet.
-    /// check and will return an appropriate [PusError] if the check fails.
     pub fn new(slice: &'raw_data [u8]) -> Result<(Self, usize), PusError> {
         let raw_data_len = slice.len();
         if raw_data_len < PUS_TC_MIN_LEN_WITHOUT_APP_DATA {
@@ -575,12 +901,12 @@ mod tests {
 
     fn base_ping_tc_simple_ctor() -> PusTcCreator<'static> {
         let mut sph = SpHeader::tc_unseg(0x02, 0x34, 0).unwrap();
-        PusTcCreator::new_simple(&mut sph, 17, 1, &[], true)
+        PusTcCreator::new_simple(&mut sph, 17, 1, None, true)
     }
 
     fn base_ping_tc_simple_ctor_with_app_data(app_data: &'static [u8]) -> PusTcCreator<'static> {
         let mut sph = SpHeader::tc_unseg(0x02, 0x34, 0).unwrap();
-        PusTcCreator::new_simple(&mut sph, 17, 1, app_data, true)
+        PusTcCreator::new_simple(&mut sph, 17, 1, Some(app_data), true)
     }
 
     #[test]
@@ -637,7 +963,7 @@ mod tests {
     #[test]
     fn test_update_func() {
         let mut sph = SpHeader::tc_unseg(0x02, 0x34, 0).unwrap();
-        let mut tc = PusTcCreator::new_simple(&mut sph, 17, 1, &[], false);
+        let mut tc = PusTcCreator::new_simple(&mut sph, 17, 1, None, false);
         assert_eq!(tc.data_len(), 0);
         tc.update_ccsds_data_len();
         assert_eq!(tc.data_len(), 6);
@@ -684,7 +1010,9 @@ mod tests {
     fn test_vec_ser_deser() {
         let pus_tc = base_ping_tc_simple_ctor();
         let mut test_vec = Vec::new();
-        let size = pus_tc.append_to_vec(&mut test_vec);
+        let size = pus_tc
+            .append_to_vec(&mut test_vec)
+            .expect("Error writing TC to vector");
         assert_eq!(size, 13);
         verify_test_tc_raw(&test_vec.as_slice());
         verify_crc_no_app_data(&test_vec.as_slice());
@@ -730,7 +1058,9 @@ mod tests {
         let pus_tc = base_ping_tc_simple_ctor_with_app_data(&[1, 2, 3]);
         verify_test_tc(&pus_tc, true, 16);
         let mut test_vec = Vec::new();
-        let size = pus_tc.append_to_vec(&mut test_vec);
+        let size = pus_tc
+            .append_to_vec(&mut test_vec)
+            .expect("Error writing TC to vector");
         assert_eq!(test_vec[11], 1);
         assert_eq!(test_vec[12], 2);
         assert_eq!(test_vec[13], 3);

src/ecss/tm.rs

@@ -19,6 +19,7 @@ use alloc::vec::Vec;
 use delegate::delegate;
 
 use crate::time::{TimeWriter, TimestampError};
+pub use legacy_tm::*;
 
 use self::zc::PusTmSecHeaderWithoutTimestamp;
 
@@ -115,7 +116,6 @@ pub mod zc {
 
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PusTmSecondaryHeader<'stamp> {
     pus_version: PusVersion,
     pub sc_time_ref_status: u8,
@@ -123,17 +123,17 @@ pub struct PusTmSecondaryHeader<'stamp> {
     pub subservice: u8,
     pub msg_counter: u16,
     pub dest_id: u16,
-    pub time_stamp: &'stamp [u8],
+    pub timestamp: &'stamp [u8],
 }
 
 impl<'stamp> PusTmSecondaryHeader<'stamp> {
-    pub fn new_simple(service: u8, subservice: u8, time_stamp: &'stamp [u8]) -> Self {
+    pub fn new_simple(service: u8, subservice: u8, timestamp: &'stamp [u8]) -> Self {
-        Self::new(service, subservice, 0, 0, time_stamp)
+        Self::new(service, subservice, 0, 0, Some(timestamp))
     }
 
     /// Like [Self::new_simple] but without a timestamp.
     pub fn new_simple_no_timestamp(service: u8, subservice: u8) -> Self {
-        Self::new(service, subservice, 0, 0, &[])
+        Self::new(service, subservice, 0, 0, None)
     }
 
     pub fn new(
@@ -141,7 +141,7 @@ impl<'stamp> PusTmSecondaryHeader<'stamp> {
         subservice: u8,
         msg_counter: u16,
         dest_id: u16,
-        time_stamp: &'stamp [u8],
+        timestamp: Option<&'stamp [u8]>,
     ) -> Self {
         PusTmSecondaryHeader {
             pus_version: PusVersion::PusC,
@@ -150,7 +150,7 @@ impl<'stamp> PusTmSecondaryHeader<'stamp> {
             subservice,
             msg_counter,
             dest_id,
-            time_stamp,
+            timestamp: timestamp.unwrap_or(&[]),
         }
     }
 }
@@ -192,11 +192,340 @@ impl<'slice> TryFrom<zc::PusTmSecHeader<'slice>> for PusTmSecondaryHeader<'slice
             subservice: sec_header.zc_header.subservice(),
             msg_counter: sec_header.zc_header.msg_counter(),
             dest_id: sec_header.zc_header.dest_id(),
-            time_stamp: sec_header.timestamp,
+            timestamp: sec_header.timestamp,
         })
     }
 }
 
+pub mod legacy_tm {
+    use crate::ecss::tm::{
+        zc, GenericPusTmSecondaryHeader, IsPusTelemetry, PusTmSecondaryHeader,
+        PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA, PUS_TM_MIN_SEC_HEADER_LEN,
+    };
+    use crate::ecss::PusVersion;
+    use crate::ecss::{
+        ccsds_impl, crc_from_raw_data, crc_procedure, sp_header_impls, user_data_from_raw,
+        verify_crc16_ccitt_false_from_raw_to_pus_error, PusError, PusPacket, WritablePusPacket,
+        CCSDS_HEADER_LEN,
+    };
+    use crate::SequenceFlags;
+    use crate::{ByteConversionError, CcsdsPacket, PacketType, SpHeader, CRC_CCITT_FALSE};
+    use core::mem::size_of;
+    use zerocopy::AsBytes;
+
+    #[cfg(feature = "serde")]
+    use serde::{Deserialize, Serialize};
+
+    #[cfg(feature = "alloc")]
+    use alloc::vec::Vec;
+    use delegate::delegate;
+
+    /// This class models the PUS C telemetry packet. It is the primary data structure to generate the
+    /// raw byte representation of PUS telemetry or to deserialize from one from raw bytes.
+    ///
+    /// This class also derives the [serde::Serialize] and [serde::Deserialize] trait if the [serde]
+    /// feature is used which allows to send around TM packets in a raw byte format using a serde
+    /// provider like [postcard](https://docs.rs/postcard/latest/postcard/).
+    ///
+    /// There is no spare bytes support yet.
+    ///
+    /// # Lifetimes
+    ///
+    /// * `'raw_data` - If the TM is not constructed from a raw slice, this will be the life time of
+    ///    a buffer where the user provided time stamp and source data will be serialized into. If it
+    ///    is, this is the lifetime of the raw byte slice it is constructed from.
+    #[derive(Eq, Debug, Copy, Clone)]
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+    pub struct PusTm<'raw_data> {
+        pub sp_header: SpHeader,
+        pub sec_header: PusTmSecondaryHeader<'raw_data>,
+        /// If this is set to false, a manual call to [PusTm::calc_own_crc16] or
+        /// [PusTm::update_packet_fields] is necessary for the serialized or cached CRC16 to be valid.
+        pub calc_crc_on_serialization: bool,
+        #[cfg_attr(feature = "serde", serde(skip))]
+        raw_data: Option<&'raw_data [u8]>,
+        source_data: &'raw_data [u8],
+        crc16: Option<u16>,
+    }
+
+    impl<'raw_data> PusTm<'raw_data> {
+        /// Generates a new struct instance.
+        ///
+        /// # Arguments
+        ///
+        /// * `sp_header` - Space packet header information. The correct packet type will be set
+        ///     automatically
+        /// * `sec_header` - Information contained in the secondary header, including the service
+        ///     and subservice type
+        /// * `app_data` - Custom application data
+        /// * `set_ccsds_len` - Can be used to automatically update the CCSDS space packet data length
+        ///     field. If this is not set to true, [PusTm::update_ccsds_data_len] can be called to set
+        ///     the correct value to this field manually
+        #[deprecated(
+            since = "0.7.0",
+            note = "Use specialized PusTmCreator or PusTmReader classes instead"
+        )]
+        pub fn new(
+            sp_header: &mut SpHeader,
+            sec_header: PusTmSecondaryHeader<'raw_data>,
+            source_data: Option<&'raw_data [u8]>,
+            set_ccsds_len: bool,
+        ) -> Self {
+            sp_header.set_packet_type(PacketType::Tm);
+            sp_header.set_sec_header_flag();
+            let mut pus_tm = PusTm {
+                sp_header: *sp_header,
+                raw_data: None,
+                source_data: source_data.unwrap_or(&[]),
+                sec_header,
+                calc_crc_on_serialization: true,
+                crc16: None,
+            };
+            if set_ccsds_len {
+                pus_tm.update_ccsds_data_len();
+            }
+            pus_tm
+        }
+
+        pub fn timestamp(&self) -> &[u8] {
+            self.sec_header.timestamp
+        }
+
+        pub fn source_data(&self) -> &[u8] {
+            self.source_data
+        }
+
+        pub fn set_dest_id(&mut self, dest_id: u16) {
+            self.sec_header.dest_id = dest_id;
+        }
+
+        pub fn set_msg_counter(&mut self, msg_counter: u16) {
+            self.sec_header.msg_counter = msg_counter
+        }
+
+        pub fn set_sc_time_ref_status(&mut self, sc_time_ref_status: u8) {
+            self.sec_header.sc_time_ref_status = sc_time_ref_status & 0b1111;
+        }
+
+        sp_header_impls!();
+
+        /// This is called automatically if the `set_ccsds_len` argument in the [PusTm::new] call was
+        /// used.
+        /// If this was not done or the time stamp or source data is set or changed after construction,
+        /// this function needs to be called to ensure that the data length field of the CCSDS header
+        /// is set correctly
+        pub fn update_ccsds_data_len(&mut self) {
+            self.sp_header.data_len =
+                self.len_written() as u16 - size_of::<crate::zc::SpHeader>() as u16 - 1;
+        }
+
+        /// This function should be called before the TM packet is serialized if
+        /// [PusTm.calc_crc_on_serialization] is set to False. It will calculate and cache the CRC16.
+        pub fn calc_own_crc16(&mut self) {
+            let mut digest = CRC_CCITT_FALSE.digest();
+            let sph_zc = crate::zc::SpHeader::from(self.sp_header);
+            digest.update(sph_zc.as_bytes());
+            let pus_tc_header =
+                zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
+            digest.update(pus_tc_header.as_bytes());
+            digest.update(self.sec_header.timestamp);
+            digest.update(self.source_data);
+            self.crc16 = Some(digest.finalize())
+        }
+
+        /// This helper function calls both [PusTm.update_ccsds_data_len] and [PusTm.calc_own_crc16]
+        pub fn update_packet_fields(&mut self) {
+            self.update_ccsds_data_len();
+            self.calc_own_crc16();
+        }
+
+        /// Append the raw PUS byte representation to a provided [alloc::vec::Vec]
+        #[cfg(feature = "alloc")]
+        #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
+        pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> Result<usize, PusError> {
+            let sph_zc = crate::zc::SpHeader::from(self.sp_header);
+            let mut appended_len = PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA;
+            appended_len += self.sec_header.timestamp.len();
+            appended_len += self.source_data.len();
+            let start_idx = vec.len();
+            let mut ser_len = 0;
+            vec.extend_from_slice(sph_zc.as_bytes());
+            ser_len += sph_zc.as_bytes().len();
+            // The PUS version is hardcoded to PUS C
+            let sec_header = zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
+            vec.extend_from_slice(sec_header.as_bytes());
+            ser_len += sec_header.as_bytes().len();
+            ser_len += self.sec_header.timestamp.len();
+            vec.extend_from_slice(self.sec_header.timestamp);
+            vec.extend_from_slice(self.source_data);
+            ser_len += self.source_data.len();
+            let crc16 = crc_procedure(
+                self.calc_crc_on_serialization,
+                &self.crc16,
+                start_idx,
+                ser_len,
+                &vec[start_idx..start_idx + ser_len],
+            )?;
+            vec.extend_from_slice(crc16.to_be_bytes().as_slice());
+            Ok(appended_len)
+        }
+
+        /// Create a [PusTm] instance from a raw slice. On success, it returns a tuple containing
+        /// the instance and the found byte length of the packet. The timestamp length needs to be
+        /// known beforehand.
+        #[deprecated(
+            since = "0.7.0",
+            note = "Use specialized PusTmCreator or PusTmReader classes instead"
+        )]
+        pub fn from_bytes(
+            slice: &'raw_data [u8],
+            timestamp_len: usize,
+        ) -> Result<(Self, usize), PusError> {
+            let raw_data_len = slice.len();
+            if raw_data_len < PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA {
+                return Err(ByteConversionError::FromSliceTooSmall {
+                    found: raw_data_len,
+                    expected: PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA,
+                }
+                .into());
+            }
+            let mut current_idx = 0;
+            let (sp_header, _) = SpHeader::from_be_bytes(&slice[0..CCSDS_HEADER_LEN])?;
+            current_idx += 6;
+            let total_len = sp_header.total_len();
+            if raw_data_len < total_len {
+                return Err(ByteConversionError::FromSliceTooSmall {
+                    found: raw_data_len,
+                    expected: PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA,
+                }
+                .into());
+            }
+            if total_len < PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA {
+                return Err(ByteConversionError::FromSliceTooSmall {
+                    found: total_len,
+                    expected: PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA,
+                }
+                .into());
+            }
+            let sec_header_zc = zc::PusTmSecHeaderWithoutTimestamp::from_bytes(
+                &slice[current_idx..current_idx + PUS_TM_MIN_SEC_HEADER_LEN],
+            )
+            .ok_or(ByteConversionError::ZeroCopyFromError)?;
+            current_idx += PUS_TM_MIN_SEC_HEADER_LEN;
+            let zc_sec_header_wrapper = zc::PusTmSecHeader {
+                zc_header: sec_header_zc,
+                timestamp: &slice[current_idx..current_idx + timestamp_len],
+            };
+            current_idx += timestamp_len;
+            let raw_data = &slice[0..total_len];
+            let pus_tm = PusTm {
+                sp_header,
+                sec_header: PusTmSecondaryHeader::try_from(zc_sec_header_wrapper).unwrap(),
+                raw_data: Some(&slice[0..total_len]),
+                source_data: user_data_from_raw(current_idx, total_len, slice)?,
+                calc_crc_on_serialization: false,
+                crc16: Some(crc_from_raw_data(raw_data)?),
+            };
+            verify_crc16_ccitt_false_from_raw_to_pus_error(
+                raw_data,
+                pus_tm.crc16.expect("CRC16 invalid"),
+            )?;
+            Ok((pus_tm, total_len))
+        }
+
+        /// If [Self] was constructed [Self::from_bytes], this function will return the slice it was
+        /// constructed from. Otherwise, [None] will be returned.
+        pub fn raw_bytes(&self) -> Option<&'raw_data [u8]> {
+            self.raw_data
+        }
+    }
+
+    impl WritablePusPacket for PusTm<'_> {
+        fn len_written(&self) -> usize {
+            PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA
+                + self.sec_header.timestamp.len()
+                + self.source_data.len()
+        }
+        /// Write the raw PUS byte representation to a provided buffer.
+        fn write_to_bytes(&self, slice: &mut [u8]) -> Result<usize, PusError> {
+            let mut curr_idx = 0;
+            let total_size = self.len_written();
+            if total_size > slice.len() {
+                return Err(ByteConversionError::ToSliceTooSmall {
+                    found: slice.len(),
+                    expected: total_size,
+                }
+                .into());
+            }
+            self.sp_header
+                .write_to_be_bytes(&mut slice[0..CCSDS_HEADER_LEN])?;
+            curr_idx += CCSDS_HEADER_LEN;
+            let sec_header_len = size_of::<zc::PusTmSecHeaderWithoutTimestamp>();
+            let sec_header = zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
+            sec_header
+                .write_to_bytes(&mut slice[curr_idx..curr_idx + sec_header_len])
+                .ok_or(ByteConversionError::ZeroCopyToError)?;
+            curr_idx += sec_header_len;
+            slice[curr_idx..curr_idx + self.sec_header.timestamp.len()]
+                .copy_from_slice(self.sec_header.timestamp);
+            curr_idx += self.sec_header.timestamp.len();
+            slice[curr_idx..curr_idx + self.source_data.len()].copy_from_slice(self.source_data);
+            curr_idx += self.source_data.len();
+            let crc16 = crc_procedure(
+                self.calc_crc_on_serialization,
+                &self.crc16,
+                0,
+                curr_idx,
+                slice,
+            )?;
+            slice[curr_idx..curr_idx + 2].copy_from_slice(crc16.to_be_bytes().as_slice());
+            curr_idx += 2;
+            Ok(curr_idx)
+        }
+    }
+
+    impl PartialEq for PusTm<'_> {
+        fn eq(&self, other: &Self) -> bool {
+            self.sp_header == other.sp_header
+                && self.sec_header == other.sec_header
+                && self.source_data == other.source_data
+        }
+    }
+
+    impl CcsdsPacket for PusTm<'_> {
+        ccsds_impl!();
+    }
+
+    impl PusPacket for PusTm<'_> {
+        delegate!(to self.sec_header {
+            fn pus_version(&self) -> PusVersion;
+            fn service(&self) -> u8;
+            fn subservice(&self) -> u8;
+        });
+
+        fn user_data(&self) -> &[u8] {
+            self.source_data
+        }
+
+        fn crc16(&self) -> Option<u16> {
+            self.crc16
+        }
+    }
+
+    impl GenericPusTmSecondaryHeader for PusTm<'_> {
+        delegate!(to self.sec_header {
+            fn pus_version(&self) -> PusVersion;
+            fn service(&self) -> u8;
+            fn subservice(&self) -> u8;
+            fn dest_id(&self) -> u16;
+            fn msg_counter(&self) -> u16;
+            fn sc_time_ref_status(&self) -> u8;
+        });
+    }
+
+    impl IsPusTelemetry for PusTm<'_> {}
+}
+
 /// This class models the PUS C telemetry packet. It is the primary data structure to generate the
 /// raw byte representation of PUS telemetry.
 ///
@@ -211,18 +540,16 @@ impl<'slice> TryFrom<zc::PusTmSecHeader<'slice>> for PusTmSecondaryHeader<'slice
 /// * `'raw_data` - This is the lifetime of the user provided time stamp and source data.
 #[derive(Eq, Debug, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub struct PusTmCreator<'raw_data> {
-pub struct PusTmCreator<'time, 'raw_data> {
     pub sp_header: SpHeader,
-    #[cfg_attr(feature = "serde", serde(borrow))]
+    pub sec_header: PusTmSecondaryHeader<'raw_data>,
-    pub sec_header: PusTmSecondaryHeader<'time>,
     source_data: &'raw_data [u8],
-    /// If this is set to false, a manual call to [Self::calc_own_crc16] or
+    /// If this is set to false, a manual call to [PusTm::calc_own_crc16] or
-    /// [Self::update_packet_fields] is necessary for the serialized or cached CRC16 to be valid.
+    /// [PusTm::update_packet_fields] is necessary for the serialized or cached CRC16 to be valid.
     pub calc_crc_on_serialization: bool,
 }
 
-impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
+impl<'raw_data> PusTmCreator<'raw_data> {
     /// Generates a new struct instance.
     ///
     /// # Arguments
@@ -233,11 +560,11 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
     ///     and subservice type
     /// * `source_data` - Custom application data
     /// * `set_ccsds_len` - Can be used to automatically update the CCSDS space packet data length
-    ///     field. If this is not set to true, [Self::update_ccsds_data_len] can be called to set
+    ///     field. If this is not set to true, [PusTm::update_ccsds_data_len] can be called to set
     ///     the correct value to this field manually
     pub fn new(
         sp_header: &mut SpHeader,
-        sec_header: PusTmSecondaryHeader<'time>,
+        sec_header: PusTmSecondaryHeader<'raw_data>,
         source_data: &'raw_data [u8],
         set_ccsds_len: bool,
     ) -> Self {
@@ -260,7 +587,7 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
         service: u8,
         subservice: u8,
         time_provider: &impl TimeWriter,
-        stamp_buf: &'time mut [u8],
+        stamp_buf: &'raw_data mut [u8],
         source_data: Option<&'raw_data [u8]>,
         set_ccsds_len: bool,
     ) -> Result<Self, TimestampError> {
@@ -277,14 +604,14 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
 
     pub fn new_no_source_data(
         sp_header: &mut SpHeader,
-        sec_header: PusTmSecondaryHeader<'time>,
+        sec_header: PusTmSecondaryHeader<'raw_data>,
         set_ccsds_len: bool,
     ) -> Self {
         Self::new(sp_header, sec_header, &[], set_ccsds_len)
     }
 
     pub fn timestamp(&self) -> &[u8] {
-        self.sec_header.time_stamp
+        self.sec_header.timestamp
     }
 
     pub fn source_data(&self) -> &[u8] {
@@ -305,7 +632,7 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
 
     sp_header_impls!();
 
-    /// This is called automatically if the `set_ccsds_len` argument in the [Self::new] call was
+    /// This is called automatically if the `set_ccsds_len` argument in the [PusTm::new] call was
     /// used.
     /// If this was not done or the time stamp or source data is set or changed after construction,
     /// this function needs to be called to ensure that the data length field of the CCSDS header
@@ -316,32 +643,60 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
     }
 
     /// This function should be called before the TM packet is serialized if
-    /// [Self::calc_crc_on_serialization] is set to False. It will calculate and cache the CRC16.
+    /// [PusTm.calc_crc_on_serialization] is set to False. It will calculate and cache the CRC16.
     pub fn calc_own_crc16(&self) -> u16 {
         let mut digest = CRC_CCITT_FALSE.digest();
         let sph_zc = crate::zc::SpHeader::from(self.sp_header);
         digest.update(sph_zc.as_bytes());
         let pus_tc_header = zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
         digest.update(pus_tc_header.as_bytes());
-        digest.update(self.sec_header.time_stamp);
+        digest.update(self.sec_header.timestamp);
         digest.update(self.source_data);
         digest.finalize()
     }
 
-    /// This helper function calls both [Self::update_ccsds_data_len] and [Self::calc_own_crc16]
+    /// This helper function calls both [PusTm.update_ccsds_data_len] and [PusTm.calc_own_crc16]
     pub fn update_packet_fields(&mut self) {
         self.update_ccsds_data_len();
     }
 
+    /// Append the raw PUS byte representation to a provided [alloc::vec::Vec]
+    #[cfg(feature = "alloc")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
+    pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> Result<usize, PusError> {
+        let sph_zc = crate::zc::SpHeader::from(self.sp_header);
+        let mut appended_len = PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA + self.sec_header.timestamp.len();
+        appended_len += self.source_data.len();
+        let start_idx = vec.len();
+        vec.extend_from_slice(sph_zc.as_bytes());
+        // The PUS version is hardcoded to PUS C
+        let sec_header = zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
+        vec.extend_from_slice(sec_header.as_bytes());
+        vec.extend_from_slice(self.sec_header.timestamp);
+        vec.extend_from_slice(self.source_data);
+        let mut digest = CRC_CCITT_FALSE.digest();
+        digest.update(&vec[start_idx..start_idx + appended_len - 2]);
+        vec.extend_from_slice(&digest.finalize().to_be_bytes());
+        Ok(appended_len)
+    }
+}
+
+impl WritablePusPacket for PusTmCreator<'_> {
+    fn len_written(&self) -> usize {
+        PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA
+            + self.sec_header.timestamp.len()
+            + self.source_data.len()
+    }
     /// Write the raw PUS byte representation to a provided buffer.
-    pub fn write_to_bytes(&self, slice: &mut [u8]) -> Result<usize, ByteConversionError> {
+    fn write_to_bytes(&self, slice: &mut [u8]) -> Result<usize, PusError> {
         let mut curr_idx = 0;
         let total_size = self.len_written();
         if total_size > slice.len() {
             return Err(ByteConversionError::ToSliceTooSmall {
                 found: slice.len(),
                 expected: total_size,
-            });
+            }
+            .into());
         }
         self.sp_header
             .write_to_be_bytes(&mut slice[0..CCSDS_HEADER_LEN])?;
@@ -352,9 +707,9 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
             .write_to_bytes(&mut slice[curr_idx..curr_idx + sec_header_len])
             .ok_or(ByteConversionError::ZeroCopyToError)?;
         curr_idx += sec_header_len;
-        slice[curr_idx..curr_idx + self.sec_header.time_stamp.len()]
+        slice[curr_idx..curr_idx + self.sec_header.timestamp.len()]
-            .copy_from_slice(self.sec_header.time_stamp);
+            .copy_from_slice(self.sec_header.timestamp);
-        curr_idx += self.sec_header.time_stamp.len();
+        curr_idx += self.sec_header.timestamp.len();
         slice[curr_idx..curr_idx + self.source_data.len()].copy_from_slice(self.source_data);
         curr_idx += self.source_data.len();
         let mut digest = CRC_CCITT_FALSE.digest();
@@ -363,41 +718,9 @@ impl<'time, 'raw_data> PusTmCreator<'time, 'raw_data> {
         curr_idx += 2;
         Ok(curr_idx)
     }
-
-    /// Append the raw PUS byte representation to a provided [alloc::vec::Vec]
-    #[cfg(feature = "alloc")]
-    pub fn append_to_vec(&self, vec: &mut Vec<u8>) -> Result<usize, PusError> {
-        let sph_zc = crate::zc::SpHeader::from(self.sp_header);
-        let mut appended_len =
-            PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA + self.sec_header.time_stamp.len();
-        appended_len += self.source_data.len();
-        let start_idx = vec.len();
-        vec.extend_from_slice(sph_zc.as_bytes());
-        // The PUS version is hardcoded to PUS C
-        let sec_header = zc::PusTmSecHeaderWithoutTimestamp::try_from(self.sec_header).unwrap();
-        vec.extend_from_slice(sec_header.as_bytes());
-        vec.extend_from_slice(self.sec_header.time_stamp);
-        vec.extend_from_slice(self.source_data);
-        let mut digest = CRC_CCITT_FALSE.digest();
-        digest.update(&vec[start_idx..start_idx + appended_len - 2]);
-        vec.extend_from_slice(&digest.finalize().to_be_bytes());
-        Ok(appended_len)
-    }
 }
 
-impl WritablePusPacket for PusTmCreator<'_, '_> {
+impl PartialEq for PusTmCreator<'_> {
-    fn len_written(&self) -> usize {
-        PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA
-            + self.sec_header.time_stamp.len()
-            + self.source_data.len()
-    }
-    /// Write the raw PUS byte representation to a provided buffer.
-    fn write_to_bytes(&self, slice: &mut [u8]) -> Result<usize, PusError> {
-        Ok(Self::write_to_bytes(self, slice)?)
-    }
-}
-
-impl PartialEq for PusTmCreator<'_, '_> {
     fn eq(&self, other: &Self) -> bool {
         self.sp_header == other.sp_header
             && self.sec_header == other.sec_header
@@ -405,11 +728,11 @@ impl PartialEq for PusTmCreator<'_, '_> {
     }
 }
 
-impl CcsdsPacket for PusTmCreator<'_, '_> {
+impl CcsdsPacket for PusTmCreator<'_> {
     ccsds_impl!();
 }
 
-impl PusPacket for PusTmCreator<'_, '_> {
+impl PusPacket for PusTmCreator<'_> {
     delegate!(to self.sec_header {
         fn pus_version(&self) -> PusVersion;
         fn service(&self) -> u8;
@@ -425,7 +748,7 @@ impl PusPacket for PusTmCreator<'_, '_> {
     }
 }
 
-impl GenericPusTmSecondaryHeader for PusTmCreator<'_, '_> {
+impl GenericPusTmSecondaryHeader for PusTmCreator<'_> {
     delegate!(to self.sec_header {
         fn pus_version(&self) -> PusVersion;
         fn service(&self) -> u8;
@@ -436,7 +759,7 @@ impl GenericPusTmSecondaryHeader for PusTmCreator<'_, '_> {
     });
 }
 
-impl IsPusTelemetry for PusTmCreator<'_, '_> {}
+impl IsPusTelemetry for PusTmCreator<'_> {}
 
 /// This class models the PUS C telemetry packet. It is the primary data structure to read
 /// a telemetry packet from raw bytes.
@@ -452,7 +775,6 @@ impl IsPusTelemetry for PusTmCreator<'_, '_> {}
 /// * `'raw_data` - Lifetime of the raw slice this class is constructed from.
 #[derive(Eq, Debug, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PusTmReader<'raw_data> {
     pub sp_header: SpHeader,
     pub sec_header: PusTmSecondaryHeader<'raw_data>,
@@ -466,9 +788,6 @@ impl<'raw_data> PusTmReader<'raw_data> {
     /// Create a [PusTmReader] instance from a raw slice. On success, it returns a tuple containing
     /// the instance and the found byte length of the packet. The timestamp length needs to be
     /// known beforehand.
-    ///
-    /// This function will check the CRC-16 of the PUS packet and will return an appropriate
-    /// [PusError] if the check fails.
     pub fn new(slice: &'raw_data [u8], timestamp_len: usize) -> Result<(Self, usize), PusError> {
         let raw_data_len = slice.len();
         if raw_data_len < PUS_TM_MIN_LEN_WITHOUT_SOURCE_DATA {
@@ -527,7 +846,7 @@ impl<'raw_data> PusTmReader<'raw_data> {
     }
 
     pub fn timestamp(&self) -> &[u8] {
-        self.sec_header.time_stamp
+        self.sec_header.timestamp
     }
 
     /// This function will return the slice [Self] was constructed from.
@@ -578,15 +897,15 @@ impl GenericPusTmSecondaryHeader for PusTmReader<'_> {
 
 impl IsPusTelemetry for PusTmReader<'_> {}
 
-impl PartialEq<PusTmCreator<'_, '_>> for PusTmReader<'_> {
+impl PartialEq<PusTmCreator<'_>> for PusTmReader<'_> {
-    fn eq(&self, other: &PusTmCreator<'_, '_>) -> bool {
+    fn eq(&self, other: &PusTmCreator<'_>) -> bool {
         self.sp_header == other.sp_header
             && self.sec_header == other.sec_header
             && self.source_data == other.source_data
     }
 }
 
-impl PartialEq<PusTmReader<'_>> for PusTmCreator<'_, '_> {
+impl PartialEq<PusTmReader<'_>> for PusTmCreator<'_> {
     fn eq(&self, other: &PusTmReader<'_>) -> bool {
         self.sp_header == other.sp_header
             && self.sec_header == other.sec_header
@@ -798,7 +1117,7 @@ mod tests {
         PusTmCreator::new(&mut sph, tm_header, DUMMY_DATA, true)
     }
 
-    fn base_hk_reply<'a, 'b>(timestamp: &'a [u8], src_data: &'b [u8]) -> PusTmCreator<'a, 'b> {
+    fn base_hk_reply<'a>(timestamp: &'a [u8], src_data: &'a [u8]) -> PusTmCreator<'a> {
         let mut sph = SpHeader::tm_unseg(0x123, 0x234, 0).unwrap();
         let tc_header = PusTmSecondaryHeader::new_simple(3, 5, timestamp);
         PusTmCreator::new(&mut sph, tc_header, src_data, true)
@@ -941,11 +1260,18 @@ mod tests {
         let res = pus_tm.write_to_bytes(&mut buf);
         assert!(res.is_err());
         let error = res.unwrap_err();
-        if let ByteConversionError::ToSliceTooSmall { found, expected } = error {
+        assert!(matches!(error, PusError::ByteConversion { .. }));
-            assert_eq!(expected, 22);
+        match error {
-            assert_eq!(found, 16);
+            PusError::ByteConversion(err) => match err {
-        } else {
+                ByteConversionError::ToSliceTooSmall { found, expected } => {
-            panic!("Invalid error {:?}", error);
+                    assert_eq!(expected, 22);
+                    assert_eq!(found, 16);
+                }
+                _ => panic!("Invalid PUS error {:?}", err),
+            },
+            _ => {
+                panic!("Invalid error {:?}", error);
+            }
         }
     }
 
@@ -1147,7 +1473,7 @@ mod tests {
     #[test]
     fn test_sec_header_without_stamp() {
         let sec_header = PusTmSecondaryHeader::new_simple_no_timestamp(17, 1);
-        assert_eq!(sec_header.time_stamp, &[]);
+        assert_eq!(sec_header.timestamp, &[]);
     }
 
     #[test]

src/lib.rs

@@ -36,11 +36,7 @@
 //! ### Optional features
 //!
 //!  - [`serde`](https://serde.rs/): Adds `serde` support for most types by adding `Serialize` and
-//!    `Deserialize` `derives.
+//!    `Deserialize` `derive`s
-//!  - [`chrono`](https://crates.io/crates/chrono): Add basic support for the `chrono` time library.
-//!  - [`timelib`](https://crates.io/crates/time): Add basic support for the `time` time library.
-//!  - [`defmt`](https://defmt.ferrous-systems.com/): Add support for the `defmt` by adding the
-//!    [`defmt::Format`](https://defmt.ferrous-systems.com/format) derive on many types.
 //!
 //! ## Module
 //!
@@ -59,7 +55,7 @@
 //! println!("{:x?}", &ccsds_buf[0..6]);
 //! ```
 #![no_std]
-#![cfg_attr(docs_rs, feature(doc_auto_cfg))]
+#![cfg_attr(doc_cfg, feature(doc_cfg))]
 #[cfg(feature = "alloc")]
 extern crate alloc;
 #[cfg(any(feature = "std", test))]
@@ -97,7 +93,6 @@ pub const MAX_SEQ_COUNT: u16 = 2u16.pow(14) - 1;
 /// Generic error type when converting to and from raw byte slices.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum ByteConversionError {
     /// The passed slice is too small. Returns the passed slice length and expected minimum size
     ToSliceTooSmall {
@@ -147,7 +142,6 @@ impl Error for ByteConversionError {}
 /// CCSDS packet type enumeration.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum PacketType {
     Tm = 0,
     Tc = 1,
@@ -171,7 +165,6 @@ pub fn packet_type_in_raw_packet_id(packet_id: u16) -> PacketType {
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum SequenceFlags {
     ContinuationSegment = 0b00,
     FirstSegment = 0b01,
@@ -199,7 +192,6 @@ impl TryFrom<u8> for SequenceFlags {
 /// of the first two bytes in the CCSDS primary header.
 #[derive(Debug, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PacketId {
     pub ptype: PacketType,
     pub sec_header_flag: bool,
@@ -311,7 +303,6 @@ impl From<u16> for PacketId {
 /// third and the fourth byte in the CCSDS primary header.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct PacketSequenceCtrl {
     pub seq_flags: SequenceFlags,
     seq_count: u16,
@@ -472,7 +463,6 @@ pub trait CcsdsPrimaryHeader {
 /// * `data_len` - Data length field occupies the fifth and the sixth byte of the raw header
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct SpHeader {
     pub version: u8,
     pub packet_id: PacketId,
@@ -808,7 +798,7 @@ pub(crate) mod tests {
         let id_default = PacketId::default();
         assert_eq!(id_default.ptype, PacketType::Tm);
         assert_eq!(id_default.apid, 0x000);
-        assert!(!id_default.sec_header_flag);
+        assert_eq!(id_default.sec_header_flag, false);
     }
 
     #[test]
@@ -818,7 +808,7 @@ pub(crate) mod tests {
         let packet_id = packet_id.unwrap();
         assert_eq!(packet_id.apid(), 0x1ff);
         assert_eq!(packet_id.ptype, PacketType::Tc);
-        assert!(packet_id.sec_header_flag);
+        assert_eq!(packet_id.sec_header_flag, true);
         let packet_id_tc = PacketId::tc(true, 0x1ff);
         assert!(packet_id_tc.is_some());
         let packet_id_tc = packet_id_tc.unwrap();

src/time/ascii.rs

@@ -40,11 +40,13 @@ pub mod alloc_mod_chrono {
     };
 
     /// Generates a time code formatter using the [FMT_STR_CODE_A_WITH_SIZE] format.
+    #[cfg_attr(doc_cfg, doc(cfg(all(feature = "alloc", feature = "chrono"))))]
     pub fn generate_time_code_a(date: &DateTime<Utc>) -> DelayedFormat<StrftimeItems<'static>> {
         date.format(FMT_STR_CODE_A_WITH_SIZE.0)
     }
 
     /// Generates a time code formatter using the [FMT_STR_CODE_A_TERMINATED_WITH_SIZE] format.
+    #[cfg_attr(doc_cfg, doc(cfg(all(feature = "alloc", feature = "chrono"))))]
     pub fn generate_time_code_a_terminated(
         date: &DateTime<Utc>,
     ) -> DelayedFormat<StrftimeItems<'static>> {
@@ -52,11 +54,13 @@ pub mod alloc_mod_chrono {
     }
 
     /// Generates a time code formatter using the [FMT_STR_CODE_B_WITH_SIZE] format.
+    #[cfg_attr(doc_cfg, doc(cfg(all(feature = "alloc", feature = "chrono"))))]
     pub fn generate_time_code_b(date: &DateTime<Utc>) -> DelayedFormat<StrftimeItems<'static>> {
         date.format(FMT_STR_CODE_B_WITH_SIZE.0)
     }
 
     /// Generates a time code formatter using the [FMT_STR_CODE_B_TERMINATED_WITH_SIZE] format.
+    #[cfg_attr(doc_cfg, doc(cfg(all(feature = "alloc", feature = "chrono"))))]
     pub fn generate_time_code_b_terminated(
         date: &DateTime<Utc>,
     ) -> DelayedFormat<StrftimeItems<'static>> {

src/time/cds.rs

@@ -1,7 +1,7 @@
 //! Module to generate or read CCSDS Day Segmented (CDS) timestamps as specified in
 //! [CCSDS 301.0-B-4](https://public.ccsds.org/Pubs/301x0b4e1.pdf) section 3.3 .
 //!
-//! The core data structure to do this is the [CdsTime] struct and the
+//! The core data structure to do this is the [TimeProvider] struct and the
 //! [get_dyn_time_provider_from_bytes] function to retrieve correct instances of the
 //! struct from a bytestream.
 use crate::private::Sealed;
@@ -34,9 +34,8 @@ use core::any::Any;
 use serde::{Deserialize, Serialize};
 
 use super::{
-    ccsds_to_unix_days, unix_to_ccsds_days, CcsdsTimeCode, CcsdsTimeProvider,
+    ccsds_to_unix_days, unix_to_ccsds_days, CcsdsTimeCode, CcsdsTimeProvider, TimeReader,
-    DateBeforeCcsdsEpochError, TimeReader, TimeWriter, TimestampError, UnixTime, MS_PER_DAY,
+    TimeWriter, TimestampError, UnixTime, MS_PER_DAY, SECONDS_PER_DAY,
-    SECONDS_PER_DAY,
 };
 
 /// Base value for the preamble field for a time field parser to determine the time field type.
@@ -59,7 +58,7 @@ pub trait ProvidesDaysLength: Sealed + Clone {
         + Into<i64>;
 }
 
-/// Type level token to be used as a generic parameter to [CdsTime].
+/// Type level token to be used as a generic parameter to [TimeProvider].
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Default)]
 pub struct DaysLen16Bits {}
 
@@ -68,7 +67,7 @@ impl ProvidesDaysLength for DaysLen16Bits {
     type FieldType = u16;
 }
 
-/// Type level token to be used as a generic parameter to [CdsTime].
+/// Type level token to be used as a generic parameter to [TimeProvider].
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Default)]
 pub struct DaysLen24Bits {}
 impl Sealed for DaysLen24Bits {}
@@ -78,7 +77,6 @@ impl ProvidesDaysLength for DaysLen24Bits {
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum LengthOfDaySegment {
     Short16Bits = 0,
     Long24Bits = 1,
@@ -95,14 +93,12 @@ pub enum SubmillisPrecision {
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum CdsError {
     /// CCSDS days value exceeds maximum allowed size or is negative
     InvalidCcsdsDays(i64),
     /// There are distinct constructors depending on the days field width detected in the preamble
     /// field. This error will be returned if there is a missmatch.
     InvalidCtorForDaysOfLenInPreamble(LengthOfDaySegment),
-    DateBeforeCcsdsEpoch(DateBeforeCcsdsEpochError),
 }
 
 impl Display for CdsError {
@@ -117,27 +113,12 @@ impl Display for CdsError {
                     "wrong constructor for length of day {length_of_day:?} detected in preamble",
                 )
             }
-            CdsError::DateBeforeCcsdsEpoch(e) => write!(f, "date before CCSDS epoch: {e}"),
         }
     }
 }
 
 #[cfg(feature = "std")]
-impl Error for CdsError {
+impl Error for CdsError {}
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        match self {
-            CdsError::DateBeforeCcsdsEpoch(e) => Some(e),
-            _ => None,
-        }
-    }
-}
-
-impl From<DateBeforeCcsdsEpochError> for CdsError {
-    fn from(value: DateBeforeCcsdsEpochError) -> Self {
-        Self::DateBeforeCcsdsEpoch(value)
-    }
-}
-
 pub fn length_of_day_segment_from_pfield(pfield: u8) -> LengthOfDaySegment {
     if (pfield >> 2) & 0b1 == 1 {
         return LengthOfDaySegment::Long24Bits;
@@ -175,19 +156,19 @@ pub fn precision_from_pfield(pfield: u8) -> SubmillisPrecision {
 ///
 /// ```
 /// use core::time::Duration;
-/// use spacepackets::time::cds::{CdsTime, length_of_day_segment_from_pfield, LengthOfDaySegment};
+/// use spacepackets::time::cds::{TimeProvider, length_of_day_segment_from_pfield, LengthOfDaySegment};
-/// use spacepackets::time::{TimeWriter, CcsdsTimeCode, CcsdsTimeProvider};
+/// use spacepackets::time::{TimeWriter, CcsdsTimeCodes, CcsdsTimeProvider};
 ///
-/// let timestamp_now = CdsTime::now_with_u16_days().unwrap();
+/// let timestamp_now = TimeProvider::from_now_with_u16_days().unwrap();
 /// let mut raw_stamp = [0; 7];
 /// {
 ///     let written = timestamp_now.write_to_bytes(&mut raw_stamp).unwrap();
-///     assert_eq!((raw_stamp[0] >> 4) & 0b111, CcsdsTimeCode::Cds as u8);
+///     assert_eq!((raw_stamp[0] >> 4) & 0b111, CcsdsTimeCodes::Cds as u8);
 ///     assert_eq!(written, 7);
 /// }
 /// {
 ///     assert_eq!(length_of_day_segment_from_pfield(raw_stamp[0]), LengthOfDaySegment::Short16Bits);
-///     let read_result = CdsTime::from_bytes_with_u16_days(&raw_stamp);
+///     let read_result = TimeProvider::from_bytes_with_u16_days(&raw_stamp);
 ///     assert!(read_result.is_ok());
 ///     let stamp_deserialized = read_result.unwrap();
 ///     assert_eq!(stamp_deserialized.len_as_bytes(), 7);
@@ -207,7 +188,7 @@ pub struct CdsTime<DaysLen: ProvidesDaysLength = DaysLen16Bits> {
     submillis: u32,
     /// This is not strictly necessary but still cached because it significantly simplifies the
     /// calculation of [`DateTime<Utc>`].
-    unix_time: UnixTime,
+    unix_stamp: UnixTime,
 }
 
 /// Common properties for all CDS time providers.
@@ -245,11 +226,11 @@ impl ConversionFromUnix {
         unix_seconds: i64,
         subsec_nanos: u32,
         precision: SubmillisPrecision,
-    ) -> Result<Self, DateBeforeCcsdsEpochError> {
+    ) -> Result<Self, TimestampError> {
         let (unix_days, secs_of_day) = calc_unix_days_and_secs_of_day(unix_seconds);
         let ccsds_days = unix_to_ccsds_days(unix_days);
         if ccsds_days == 0 && (secs_of_day > 0 || subsec_nanos > 0) || ccsds_days < 0 {
-            return Err(DateBeforeCcsdsEpochError(
+            return Err(TimestampError::DateBeforeCcsdsEpoch(
                 UnixTime::new_checked(unix_seconds, subsec_nanos)
                     .expect("unix timestamp creation failed"),
             ));
@@ -337,19 +318,19 @@ fn calc_unix_days_and_secs_of_day(unix_seconds: i64) -> (i64, u32) {
 
 #[cfg(feature = "chrono")]
 impl ConversionFromChronoDatetime {
-    fn new(dt: &chrono::DateTime<chrono::Utc>) -> Result<Self, DateBeforeCcsdsEpochError> {
+    fn new(dt: &chrono::DateTime<chrono::Utc>) -> Result<Self, TimestampError> {
         Self::new_generic(dt, SubmillisPrecision::Absent)
     }
 
     fn new_with_submillis_us_prec(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, DateBeforeCcsdsEpochError> {
+    ) -> Result<Self, TimestampError> {
         Self::new_generic(dt, SubmillisPrecision::Microseconds)
     }
 
     fn new_with_submillis_ps_prec(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, DateBeforeCcsdsEpochError> {
+    ) -> Result<Self, TimestampError> {
         Self::new_generic(dt, SubmillisPrecision::Picoseconds)
     }
 
@@ -357,10 +338,10 @@ impl ConversionFromChronoDatetime {
     fn new_generic(
         dt: &chrono::DateTime<chrono::Utc>,
         prec: SubmillisPrecision,
-    ) -> Result<Self, DateBeforeCcsdsEpochError> {
+    ) -> Result<Self, TimestampError> {
         // The CDS timestamp does not support timestamps before the CCSDS epoch.
         if dt.year() < 1958 {
-            return Err(DateBeforeCcsdsEpochError(UnixTime::from(*dt)));
+            return Err(TimestampError::DateBeforeCcsdsEpoch(UnixTime::from(*dt)));
         }
         // The contained values in the conversion should be all positive now
         let unix_conversion =
@@ -453,28 +434,31 @@ impl CdsConverter for ConversionFromNow {
 }
 
 #[cfg(feature = "alloc")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
 pub trait DynCdsTimeProvider: CcsdsTimeProvider + CdsTimestamp + TimeWriter + Any {}
 #[cfg(feature = "alloc")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
 impl DynCdsTimeProvider for CdsTime<DaysLen16Bits> {}
 #[cfg(feature = "alloc")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
 impl DynCdsTimeProvider for CdsTime<DaysLen24Bits> {}
 
-/// This function returns the correct [CdsTime] instance from a raw byte array
+/// This function returns the correct [TimeProvider] instance from a raw byte array
 /// by checking the length of days field. It also checks the CCSDS time code for correctness.
 ///
 /// # Example
 ///
 /// ```
 /// use spacepackets::time::cds::{
-///     CdsTime, LengthOfDaySegment, get_dyn_time_provider_from_bytes, SubmillisPrecision,
+///     TimeProvider, LengthOfDaySegment, get_dyn_time_provider_from_bytes, SubmillisPrecision,
 /// };
-/// use spacepackets::time::{TimeWriter, CcsdsTimeCode, CcsdsTimeProvider};
+/// use spacepackets::time::{TimeWriter, CcsdsTimeCodes, CcsdsTimeProvider};
 ///
-/// let timestamp_now = CdsTime::new_with_u16_days(24, 24);
+/// let timestamp_now = TimeProvider::new_with_u16_days(24, 24);
 /// let mut raw_stamp = [0; 7];
 /// {
 ///     let written = timestamp_now.write_to_bytes(&mut raw_stamp).unwrap();
-///     assert_eq!((raw_stamp[0] >> 4) & 0b111, CcsdsTimeCode::Cds as u8);
+///     assert_eq!((raw_stamp[0] >> 4) & 0b111, CcsdsTimeCodes::Cds as u8);
 ///     assert_eq!(written, 7);
 /// }
 /// {
@@ -486,6 +470,7 @@ impl DynCdsTimeProvider for CdsTime<DaysLen24Bits> {}
 /// }
 /// ```
 #[cfg(feature = "alloc")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
 pub fn get_dyn_time_provider_from_bytes(
     buf: &[u8],
 ) -> Result<Box<dyn DynCdsTimeProvider>, TimestampError> {
@@ -656,7 +641,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
         if let Some(precision) = self.precision_as_ns() {
             subsec_nanos += precision;
         }
-        self.unix_time = UnixTime::new(unix_days_seconds, subsec_nanos);
+        self.unix_stamp = UnixTime::new(unix_days_seconds, subsec_nanos);
     }
 
     fn length_check(&self, buf: &[u8], len_as_bytes: usize) -> Result<(), TimestampError> {
@@ -683,7 +668,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
             pfield: Self::generate_p_field(days_len, SubmillisPrecision::Absent),
             ccsds_days,
             ms_of_day,
-            unix_time: Default::default(),
+            unix_stamp: Default::default(),
             submillis: 0,
         };
         let unix_days_seconds = ccsds_to_unix_days(i64::from(ccsds_days)) * SECONDS_PER_DAY as i64;
@@ -695,7 +680,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
     fn from_dt_generic(
         dt: &chrono::DateTime<chrono::Utc>,
         days_len: LengthOfDaySegment,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         let conv_from_dt = ConversionFromChronoDatetime::new(dt)?;
         Self::generic_from_conversion(days_len, conv_from_dt)
     }
@@ -704,7 +689,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
     fn from_dt_generic_us_prec(
         dt: &chrono::DateTime<chrono::Utc>,
         days_len: LengthOfDaySegment,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         let conv_from_dt = ConversionFromChronoDatetime::new_with_submillis_us_prec(dt)?;
         Self::generic_from_conversion(days_len, conv_from_dt)
     }
@@ -713,7 +698,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
     fn from_dt_generic_ps_prec(
         dt: &chrono::DateTime<chrono::Utc>,
         days_len: LengthOfDaySegment,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         let conv_from_dt = ConversionFromChronoDatetime::new_with_submillis_ps_prec(dt)?;
         Self::generic_from_conversion(days_len, conv_from_dt)
     }
@@ -722,46 +707,48 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
         unix_stamp: &UnixTime,
         days_len: LengthOfDaySegment,
         submillis_prec: SubmillisPrecision,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         let conv_from_dt =
             ConversionFromUnix::new(unix_stamp.secs, unix_stamp.subsec_nanos, submillis_prec)?;
         Self::generic_from_conversion(days_len, conv_from_dt)
     }
 
     #[cfg(feature = "std")]
-    fn now_generic(days_len: LengthOfDaySegment) -> Result<Self, StdTimestampError> {
+    fn from_now_generic(days_len: LengthOfDaySegment) -> Result<Self, StdTimestampError> {
         let conversion_from_now = ConversionFromNow::new()?;
         Self::generic_from_conversion(days_len, conversion_from_now)
-            .map_err(|e| StdTimestampError::Timestamp(TimestampError::from(e)))
+            .map_err(StdTimestampError::Timestamp)
     }
 
     #[cfg(feature = "std")]
-    fn now_generic_with_us_prec(days_len: LengthOfDaySegment) -> Result<Self, StdTimestampError> {
+    fn from_now_generic_us_prec(days_len: LengthOfDaySegment) -> Result<Self, StdTimestampError> {
         let conversion_from_now = ConversionFromNow::new_with_submillis_us_prec()?;
         Self::generic_from_conversion(days_len, conversion_from_now)
-            .map_err(|e| StdTimestampError::Timestamp(TimestampError::from(e)))
+            .map_err(StdTimestampError::Timestamp)
     }
 
     #[cfg(feature = "std")]
     fn from_now_generic_ps_prec(days_len: LengthOfDaySegment) -> Result<Self, StdTimestampError> {
         let conversion_from_now = ConversionFromNow::new_with_submillis_ps_prec()?;
         Self::generic_from_conversion(days_len, conversion_from_now)
-            .map_err(|e| StdTimestampError::Timestamp(TimestampError::from(e)))
+            .map_err(StdTimestampError::Timestamp)
     }
 
     fn generic_from_conversion<C: CdsConverter>(
         days_len: LengthOfDaySegment,
         converter: C,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
-        let ccsds_days: ProvidesDaysLen::FieldType = converter
+        let ccsds_days: ProvidesDaysLen::FieldType =
-            .ccsds_days_as_u32()
+            converter.ccsds_days_as_u32().try_into().map_err(|_| {
-            .try_into()
+                TimestampError::Cds(CdsError::InvalidCcsdsDays(
-            .map_err(|_| CdsError::InvalidCcsdsDays(converter.ccsds_days_as_u32().into()))?;
+                    converter.ccsds_days_as_u32().into(),
+                ))
+            })?;
         let mut provider = Self {
             pfield: Self::generate_p_field(days_len, converter.submillis_precision()),
             ccsds_days,
             ms_of_day: converter.ms_of_day(),
-            unix_time: Default::default(),
+            unix_stamp: Default::default(),
             submillis: converter.submillis(),
         };
         provider.setup(converter.unix_days_seconds(), converter.ms_of_day());
@@ -789,6 +776,7 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CdsTime<ProvidesDaysLen> {
     }
 
     #[cfg(feature = "std")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
     pub fn update_from_now(&mut self) -> Result<(), StdTimestampError> {
         let conversion_from_now = self.generic_conversion_from_now()?;
         let ccsds_days: ProvidesDaysLen::FieldType = conversion_from_now
@@ -824,19 +812,22 @@ impl CdsTime<DaysLen24Bits> {
 
     /// Generate a time stamp from the current time using the system clock.
     #[cfg(feature = "std")]
-    pub fn now_with_u24_days() -> Result<Self, StdTimestampError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-        Self::now_generic(LengthOfDaySegment::Long24Bits)
+    pub fn from_now_with_u24_days() -> Result<Self, StdTimestampError> {
+        Self::from_now_generic(LengthOfDaySegment::Long24Bits)
     }
 
-    /// Create a provider from a [`chrono::DateTime<chrono::Utc>`] struct.
+    /// Create a provider from a [`DateTime<Utc>`] struct.
     ///
     /// ## Errors
     ///
-    /// This function will return [CdsError::DateBeforeCcsdsEpoch] if the time is before the CCSDS
+    /// This function will return [TimestampError::DateBeforeCcsdsEpoch] or
-    /// epoch (1958-01-01T00:00:00+00:00) or the CCSDS days value exceeds the allowed bit width
+    /// [TimestampError::Cds] if the time is before the CCSDS epoch (1958-01-01T00:00:00+00:00)
-    /// (24 bits).
+    /// or the CCSDS days value exceeds the allowed bit width (24 bits).
     #[cfg(feature = "chrono")]
-    pub fn from_dt_with_u24_days(dt: &chrono::DateTime<chrono::Utc>) -> Result<Self, CdsError> {
+    pub fn from_dt_with_u24_days(
+        dt: &chrono::DateTime<chrono::Utc>,
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic(dt, LengthOfDaySegment::Long24Bits)
     }
 
@@ -844,13 +835,13 @@ impl CdsTime<DaysLen24Bits> {
     ///
     /// ## Errors
     ///
-    /// This function will return [CdsError::DateBeforeCcsdsEpoch] if the time is before the CCSDS
+    /// This function will return [TimestampError::DateBeforeCcsdsEpoch] or
-    /// epoch (1958-01-01T00:00:00+00:00) or the CCSDS days value exceeds the allowed bit width
+    /// [TimestampError::Cds] if the time is before the CCSDS epoch (1958-01-01T00:00:00+00:00)
-    /// (24 bits).
+    /// or the CCSDS days value exceeds the allowed bit width (24 bits).
-    pub fn from_unix_time_with_u24_day(
+    pub fn from_unix_stamp_with_u24_days(
         unix_stamp: &UnixTime,
         submillis_prec: SubmillisPrecision,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_unix_generic(unix_stamp, LengthOfDaySegment::Long24Bits, submillis_prec)
     }
 
@@ -858,7 +849,7 @@ impl CdsTime<DaysLen24Bits> {
     #[cfg(feature = "chrono")]
     pub fn from_dt_with_u24_days_us_precision(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic_us_prec(dt, LengthOfDaySegment::Long24Bits)
     }
 
@@ -866,20 +857,22 @@ impl CdsTime<DaysLen24Bits> {
     #[cfg(feature = "chrono")]
     pub fn from_dt_with_u24_days_ps_precision(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic_ps_prec(dt, LengthOfDaySegment::Long24Bits)
     }
 
-    /// Like [Self::now_with_u24_days] but with microsecond sub-millisecond precision.
+    /// Like [Self::from_now_with_u24_days] but with microsecond sub-millisecond precision.
     #[cfg(feature = "std")]
-    pub fn now_with_u24_days_us_precision() -> Result<Self, StdTimestampError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-        Self::now_generic_with_us_prec(LengthOfDaySegment::Long24Bits)
+    pub fn from_now_with_u24_days_us_precision() -> Result<Self, StdTimestampError> {
+        Self::from_now_generic_us_prec(LengthOfDaySegment::Long24Bits)
     }
 
-    /// Like [Self::now_with_u24_days] but with picoseconds sub-millisecond precision.
+    /// Like [Self::from_now_with_u24_days] but with picoseconds sub-millisecond precision.
     #[cfg(feature = "std")]
-    pub fn now_with_u24_days_ps_precision() -> Result<Self, StdTimestampError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-        Self::now_generic_with_us_prec(LengthOfDaySegment::Long24Bits)
+    pub fn from_now_with_u24_days_ps_precision() -> Result<Self, StdTimestampError> {
+        Self::from_now_generic_us_prec(LengthOfDaySegment::Long24Bits)
     }
 
     pub fn from_bytes_with_u24_days(buf: &[u8]) -> Result<Self, TimestampError> {
@@ -916,33 +909,36 @@ impl CdsTime<DaysLen16Bits> {
         Self::generic_new(LengthOfDaySegment::Short16Bits, ccsds_days, ms_of_day).unwrap()
     }
 
-    /// Create a provider from a [`chrono::DateTime<Utc>`] struct.
+    /// Create a provider from a [`DateTime<Utc>`] struct.
     ///
-    /// This function will return a [CdsError::DateBeforeCcsdsEpoch] if the time is before the
+    /// This function will return a [TimestampError::DateBeforeCcsdsEpoch] or a
-    /// CCSDS epoch (01-01-1958 00:00:00) or the CCSDS days value exceeds the allowed bit width
+    /// [TimestampError::Cds] if the time is before the CCSDS epoch (01-01-1958 00:00:00) or
-    /// (16 bits).
+    /// the CCSDS days value exceeds the allowed bit width (16 bits).
     #[cfg(feature = "chrono")]
-    pub fn from_dt_with_u16_days(dt: &chrono::DateTime<chrono::Utc>) -> Result<Self, CdsError> {
+    pub fn from_dt_with_u16_days(
+        dt: &chrono::DateTime<chrono::Utc>,
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic(dt, LengthOfDaySegment::Short16Bits)
     }
 
     /// Generate a time stamp from the current time using the system clock.
     #[cfg(feature = "std")]
-    pub fn now_with_u16_days() -> Result<Self, StdTimestampError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-        Self::now_generic(LengthOfDaySegment::Short16Bits)
+    pub fn from_now_with_u16_days() -> Result<Self, StdTimestampError> {
+        Self::from_now_generic(LengthOfDaySegment::Short16Bits)
     }
 
     /// Create a provider from a generic UNIX timestamp (seconds since 1970-01-01T00:00:00+00:00).
     ///
     /// ## Errors
     ///
-    /// This function will return [CdsError::DateBeforeCcsdsEpoch] if the time is before the CCSDS
+    /// This function will return [TimestampError::DateBeforeCcsdsEpoch] or
-    /// epoch (1958-01-01T00:00:00+00:00) or the CCSDS days value exceeds the allowed bit width
+    /// [TimestampError::Cds] if the time is before the CCSDS epoch (1958-01-01T00:00:00+00:00)
-    /// (24 bits).
+    /// or the CCSDS days value exceeds the allowed bit width (24 bits).
-    pub fn from_unix_time_with_u16_days(
+    pub fn from_unix_stamp_with_u16_days(
         unix_stamp: &UnixTime,
         submillis_prec: SubmillisPrecision,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_unix_generic(unix_stamp, LengthOfDaySegment::Short16Bits, submillis_prec)
     }
 
@@ -950,7 +946,7 @@ impl CdsTime<DaysLen16Bits> {
     #[cfg(feature = "chrono")]
     pub fn from_dt_with_u16_days_us_precision(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic_us_prec(dt, LengthOfDaySegment::Short16Bits)
     }
 
@@ -958,18 +954,20 @@ impl CdsTime<DaysLen16Bits> {
     #[cfg(feature = "chrono")]
     pub fn from_dt_with_u16_days_ps_precision(
         dt: &chrono::DateTime<chrono::Utc>,
-    ) -> Result<Self, CdsError> {
+    ) -> Result<Self, TimestampError> {
         Self::from_dt_generic_ps_prec(dt, LengthOfDaySegment::Short16Bits)
     }
 
-    /// Like [Self::now_with_u16_days] but with microsecond sub-millisecond precision.
+    /// Like [Self::from_now_with_u16_days] but with microsecond sub-millisecond precision.
     #[cfg(feature = "std")]
-    pub fn now_with_u16_days_us_precision() -> Result<Self, StdTimestampError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-        Self::now_generic_with_us_prec(LengthOfDaySegment::Short16Bits)
+    pub fn from_now_with_u16_days_us_precision() -> Result<Self, StdTimestampError> {
+        Self::from_now_generic_us_prec(LengthOfDaySegment::Short16Bits)
     }
 
-    /// Like [Self::now_with_u16_days] but with picosecond sub-millisecond precision.
+    /// Like [Self::from_now_with_u16_days] but with picosecond sub-millisecond precision.
     #[cfg(feature = "std")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
     pub fn from_now_with_u16_days_ps_precision() -> Result<Self, StdTimestampError> {
         Self::from_now_generic_ps_prec(LengthOfDaySegment::Short16Bits)
     }
@@ -1170,7 +1168,7 @@ impl AddAssign<Duration> for CdsTime<DaysLen24Bits> {
 
 #[cfg(feature = "chrono")]
 impl TryFrom<chrono::DateTime<chrono::Utc>> for CdsTime<DaysLen16Bits> {
-    type Error = CdsError;
+    type Error = TimestampError;
 
     fn try_from(dt: chrono::DateTime<chrono::Utc>) -> Result<Self, Self::Error> {
         let conversion = ConversionFromChronoDatetime::new(&dt)?;
@@ -1180,7 +1178,8 @@ impl TryFrom<chrono::DateTime<chrono::Utc>> for CdsTime<DaysLen16Bits> {
 
 #[cfg(feature = "chrono")]
 impl TryFrom<chrono::DateTime<chrono::Utc>> for CdsTime<DaysLen24Bits> {
-    type Error = CdsError;
+    type Error = TimestampError;
+
     fn try_from(dt: chrono::DateTime<chrono::Utc>) -> Result<Self, Self::Error> {
         let conversion = ConversionFromChronoDatetime::new(&dt)?;
         Self::generic_from_conversion(LengthOfDaySegment::Long24Bits, conversion)
@@ -1202,16 +1201,16 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CcsdsTimeProvider for CdsTime<Provides
 
     #[inline]
     fn unix_secs(&self) -> i64 {
-        self.unix_time.secs
+        self.unix_stamp.secs
     }
     #[inline]
     fn subsec_nanos(&self) -> u32 {
-        self.unix_time.subsec_nanos
+        self.unix_stamp.subsec_nanos
     }
 
     #[inline]
-    fn unix_time(&self) -> UnixTime {
+    fn unix_stamp(&self) -> UnixTime {
-        self.unix_time
+        self.unix_stamp
     }
 }
 
@@ -1358,7 +1357,7 @@ mod tests {
     #[test]
     fn test_time_stamp_zero_args() {
         let time_stamper = CdsTime::new_with_u16_days(0, 0);
-        let unix_stamp = time_stamper.unix_time();
+        let unix_stamp = time_stamper.unix_stamp();
         assert_eq!(
             unix_stamp.secs,
             (DAYS_CCSDS_TO_UNIX * SECONDS_PER_DAY as i32) as i64
@@ -1387,7 +1386,7 @@ mod tests {
     #[test]
     fn test_time_stamp_unix_epoch() {
         let time_stamper = CdsTime::new_with_u16_days((-DAYS_CCSDS_TO_UNIX) as u16, 0);
-        assert_eq!(time_stamper.unix_time().secs, 0);
+        assert_eq!(time_stamper.unix_stamp().secs, 0);
         assert_eq!(
             time_stamper.submillis_precision(),
             SubmillisPrecision::Absent
@@ -1464,7 +1463,7 @@ mod tests {
     fn test_write() {
         let mut buf = [0; 16];
         let time_stamper_0 = CdsTime::new_with_u16_days(0, 0);
-        let unix_stamp = time_stamper_0.unix_time();
+        let unix_stamp = time_stamper_0.unix_stamp();
         assert_eq!(
             unix_stamp.secs,
             (DAYS_CCSDS_TO_UNIX * SECONDS_PER_DAY as i32).into()
@@ -1610,14 +1609,14 @@ mod tests {
 
     #[test]
     fn test_time_now() {
-        let timestamp_now = CdsTime::now_with_u16_days().unwrap();
+        let timestamp_now = CdsTime::from_now_with_u16_days().unwrap();
         let compare_stamp = chrono::Utc::now();
         generic_now_test(timestamp_now, compare_stamp);
     }
 
     #[test]
     fn test_time_now_us_prec() {
-        let timestamp_now = CdsTime::now_with_u16_days_us_precision().unwrap();
+        let timestamp_now = CdsTime::from_now_with_u16_days_us_precision().unwrap();
         let compare_stamp = chrono::Utc::now();
         generic_now_test(timestamp_now, compare_stamp);
     }
@@ -1638,7 +1637,7 @@ mod tests {
 
     #[test]
     fn test_time_now_ps_prec_u24_days() {
-        let timestamp_now = CdsTime::now_with_u24_days_ps_precision().unwrap();
+        let timestamp_now = CdsTime::from_now_with_u24_days_ps_precision().unwrap();
         let compare_stamp = chrono::Utc::now();
         generic_now_test(timestamp_now, compare_stamp);
     }
@@ -1923,7 +1922,7 @@ mod tests {
     fn test_creation_from_unix_stamp_0_u16_days() {
         let unix_secs = 0;
         let subsec_millis = 0;
-        let time_provider = CdsTime::from_unix_time_with_u16_days(
+        let time_provider = CdsTime::from_unix_stamp_with_u16_days(
             &UnixTime::new(unix_secs, subsec_millis),
             SubmillisPrecision::Absent,
         )
@@ -1935,7 +1934,7 @@ mod tests {
     fn test_creation_from_unix_stamp_0_u24_days() {
         let unix_secs = 0;
         let subsec_millis = 0;
-        let time_provider = CdsTime::from_unix_time_with_u24_day(
+        let time_provider = CdsTime::from_unix_stamp_with_u24_days(
             &UnixTime::new(unix_secs, subsec_millis),
             SubmillisPrecision::Absent,
         )
@@ -1952,9 +1951,11 @@ mod tests {
             .unwrap()
             .and_local_timezone(chrono::Utc)
             .unwrap();
-        let time_provider =
+        let time_provider = CdsTime::from_unix_stamp_with_u16_days(
-            CdsTime::from_unix_time_with_u16_days(&datetime_utc.into(), SubmillisPrecision::Absent)
+            &datetime_utc.into(),
-                .expect("creating provider from unix stamp failed");
+            SubmillisPrecision::Absent,
+        )
+        .expect("creating provider from unix stamp failed");
         // https://www.timeanddate.com/date/durationresult.html?d1=01&m1=01&y1=1958&d2=14&m2=01&y2=2023
         // Leap years need to be accounted for as well.
         assert_eq!(time_provider.ccsds_days, 23754);
@@ -1970,7 +1971,7 @@ mod tests {
     fn test_creation_0_ccsds_days() {
         let unix_secs = DAYS_CCSDS_TO_UNIX as i64 * SECONDS_PER_DAY as i64;
         let subsec_millis = 0;
-        let time_provider = CdsTime::from_unix_time_with_u16_days(
+        let time_provider = CdsTime::from_unix_stamp_with_u16_days(
             &UnixTime::new(unix_secs, subsec_millis),
             SubmillisPrecision::Absent,
         )
@@ -1982,7 +1983,7 @@ mod tests {
     fn test_invalid_creation_from_unix_stamp_days_too_large() {
         let invalid_unix_secs: i64 = (u16::MAX as i64 + 1) * SECONDS_PER_DAY as i64;
         let subsec_millis = 0;
-        match CdsTime::from_unix_time_with_u16_days(
+        match CdsTime::from_unix_stamp_with_u16_days(
             &UnixTime::new(invalid_unix_secs, subsec_millis),
             SubmillisPrecision::Absent,
         ) {
@@ -1990,12 +1991,12 @@ mod tests {
                 panic!("creation should not succeed")
             }
             Err(e) => {
-                if let CdsError::InvalidCcsdsDays(days) = e {
+                if let TimestampError::Cds(CdsError::InvalidCcsdsDays(days)) = e {
                     assert_eq!(
                         days,
                         unix_to_ccsds_days(invalid_unix_secs / SECONDS_PER_DAY as i64)
                     );
-                    assert_eq!(e.to_string(), "invalid ccsds days 69919");
+                    assert_eq!(e.to_string(), "cds error: invalid ccsds days 69919");
                 } else {
                     panic!("unexpected error {}", e)
                 }
@@ -2009,7 +2010,7 @@ mod tests {
         // precisely 31-12-1957 23:59:55
         let unix_secs = DAYS_CCSDS_TO_UNIX * SECONDS_PER_DAY as i32 - 5;
         let subsec_millis = 0;
-        match CdsTime::from_unix_time_with_u16_days(
+        match CdsTime::from_unix_stamp_with_u16_days(
             &UnixTime::new(unix_secs as i64, subsec_millis),
             SubmillisPrecision::Absent,
         ) {
@@ -2017,8 +2018,8 @@ mod tests {
                 panic!("creation should not succeed")
             }
             Err(e) => {
-                if let CdsError::DateBeforeCcsdsEpoch(DateBeforeCcsdsEpochError(unix_dt)) = e {
+                if let TimestampError::DateBeforeCcsdsEpoch(dt) = e {
-                    let dt = unix_dt.chrono_date_time();
+                    let dt = dt.chrono_date_time();
                     if let chrono::LocalResult::Single(dt) = dt {
                         assert_eq!(dt.year(), 1957);
                         assert_eq!(dt.month(), 12);
@@ -2248,9 +2249,7 @@ mod tests {
             .unwrap();
         let time_provider = CdsTime::from_dt_with_u24_days(&datetime_utc);
         assert!(time_provider.is_err());
-        if let CdsError::DateBeforeCcsdsEpoch(DateBeforeCcsdsEpochError(dt)) =
+        if let TimestampError::DateBeforeCcsdsEpoch(dt) = time_provider.unwrap_err() {
-            time_provider.unwrap_err()
-        {
             assert_eq!(dt, datetime_utc.into());
         }
     }
@@ -2296,7 +2295,7 @@ mod tests {
     fn test_update_from_now() {
         let mut stamp = CdsTime::new_with_u16_days(0, 0);
         let _ = stamp.update_from_now();
-        let dt = stamp.unix_time().chrono_date_time().unwrap();
+        let dt = stamp.unix_stamp().chrono_date_time().unwrap();
         assert!(dt.year() > 2020);
     }
 
@@ -2309,7 +2308,7 @@ mod tests {
     #[test]
     #[cfg(feature = "serde")]
     fn test_serialization() {
-        let stamp_now = CdsTime::now_with_u16_days().expect("Error retrieving time");
+        let stamp_now = CdsTime::from_now_with_u16_days().expect("Error retrieving time");
         let val = to_allocvec(&stamp_now).expect("Serializing timestamp failed");
         assert!(val.len() > 0);
         let stamp_deser: CdsTime = from_bytes(&val).expect("Stamp deserialization failed");

src/time/mod.rs

@@ -1,7 +1,7 @@
 //! CCSDS Time Code Formats according to [CCSDS 301.0-B-4](https://public.ccsds.org/Pubs/301x0b4e1.pdf)
 use crate::ByteConversionError;
 #[cfg(feature = "chrono")]
-use chrono::{TimeZone, Utc};
+use chrono::{DateTime, LocalResult, TimeZone, Utc};
 use core::cmp::Ordering;
 use core::fmt::{Display, Formatter};
 use core::ops::{Add, AddAssign, Sub};
@@ -33,7 +33,6 @@ pub const NANOS_PER_SECOND: u32 = 1_000_000_000;
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum CcsdsTimeCode {
     CucCcsdsEpoch = 0b001,
     CucAgencyEpoch = 0b010,
@@ -66,27 +65,13 @@ pub fn ccsds_time_code_from_p_field(pfield: u8) -> Result<CcsdsTimeCode, u8> {
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
-pub struct DateBeforeCcsdsEpochError(UnixTime);
-
-impl Display for DateBeforeCcsdsEpochError {
-    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
-        write!(f, "date before ccsds epoch: {:?}", self.0)
-    }
-}
-
-#[cfg(feature = "std")]
-impl Error for DateBeforeCcsdsEpochError {}
-
-#[derive(Debug, PartialEq, Eq, Copy, Clone)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
 pub enum TimestampError {
     InvalidTimeCode { expected: CcsdsTimeCode, found: u8 },
     ByteConversion(ByteConversionError),
     Cds(cds::CdsError),
     Cuc(cuc::CucError),
+    DateBeforeCcsdsEpoch(UnixTime),
     CustomEpochNotSupported,
 }
 
@@ -108,6 +93,9 @@ impl Display for TimestampError {
             TimestampError::ByteConversion(e) => {
                 write!(f, "time stamp: {e}")
             }
+            TimestampError::DateBeforeCcsdsEpoch(e) => {
+                write!(f, "datetime with date before ccsds epoch: {e:?}")
+            }
             TimestampError::CustomEpochNotSupported => {
                 write!(f, "custom epochs are not supported")
             }
@@ -126,7 +114,6 @@ impl Error for TimestampError {
         }
     }
 }
-
 impl From<cds::CdsError> for TimestampError {
     fn from(e: cds::CdsError) -> Self {
         TimestampError::Cds(e)
@@ -140,6 +127,7 @@ impl From<cuc::CucError> for TimestampError {
 }
 
 #[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
 pub mod std_mod {
     use crate::time::TimestampError;
     use std::time::SystemTimeError;
@@ -147,7 +135,7 @@ pub mod std_mod {
 
     #[derive(Debug, Clone, Error)]
     pub enum StdTimestampError {
-        #[error("system time error: {0:?}")]
+        #[error("system time error: {0}")]
         SystemTime(#[from] SystemTimeError),
         #[error("timestamp error: {0}")]
         Timestamp(#[from] TimestampError),
@@ -155,6 +143,7 @@ pub mod std_mod {
 }
 
 #[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
 pub fn seconds_since_epoch() -> f64 {
     SystemTime::now()
         .duration_since(SystemTime::UNIX_EPOCH)
@@ -189,6 +178,7 @@ pub const fn ccsds_epoch_to_unix_epoch(ccsds_epoch: i64) -> i64 {
 }
 
 #[cfg(feature = "std")]
+#[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
 pub fn ms_of_day_using_sysclock() -> u32 {
     ms_of_day(seconds_since_epoch())
 }
@@ -209,6 +199,7 @@ pub trait TimeWriter {
     fn write_to_bytes(&self, bytes: &mut [u8]) -> Result<usize, TimestampError>;
 
     #[cfg(feature = "alloc")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
     fn to_vec(&self) -> Result<alloc::vec::Vec<u8>, TimestampError> {
         let mut vec = alloc::vec![0; self.len_written()];
         self.write_to_bytes(&mut vec)?;
@@ -242,16 +233,18 @@ pub trait CcsdsTimeProvider {
         (self.subsec_nanos() / 1_000_000) as u16
     }
 
-    fn unix_time(&self) -> UnixTime {
+    fn unix_stamp(&self) -> UnixTime {
         UnixTime::new(self.unix_secs(), self.subsec_nanos())
     }
 
     #[cfg(feature = "chrono")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
     fn chrono_date_time(&self) -> chrono::LocalResult<chrono::DateTime<chrono::Utc>> {
         chrono::Utc.timestamp_opt(self.unix_secs(), self.subsec_nanos())
     }
 
     #[cfg(feature = "timelib")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "timelib")))]
     fn timelib_date_time(&self) -> Result<time::OffsetDateTime, time::error::ComponentRange> {
         Ok(time::OffsetDateTime::from_unix_timestamp(self.unix_secs())?
             + time::Duration::nanoseconds(self.subsec_nanos().into()))
@@ -265,7 +258,6 @@ pub trait CcsdsTimeProvider {
 /// similarly to other common time formats and libraries.
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct UnixTime {
     secs: i64,
     subsec_nanos: u32,
@@ -309,7 +301,7 @@ impl UnixTime {
     }
 
     /// This function will panic if the subsecond value is larger than the fraction of a second.
-    /// Use [Self::new_checked] if you want to handle this case without a panic.
+    /// Use [new_checked] if you want to handle this case without a panic.
     pub const fn new(unix_seconds: i64, subsecond_nanos: u32) -> Self {
         if subsecond_nanos >= NANOS_PER_SECOND {
             panic!("invalid subsecond nanos value");
@@ -321,7 +313,7 @@ impl UnixTime {
     }
 
     /// This function will panic if the subsecond value is larger than the fraction of a second.
-    /// Use [Self::new_subsec_millis_checked] if you want to handle this case without a panic.
+    /// Use [new_subsecond_millis_checked] if you want to handle this case without a panic.
     pub const fn new_subsec_millis(unix_seconds: i64, subsecond_millis: u16) -> Self {
         if subsecond_millis >= 1000 {
             panic!("invalid subsecond millisecond value");
@@ -349,7 +341,8 @@ impl UnixTime {
     }
 
     #[cfg(feature = "std")]
-    pub fn now() -> Result<Self, SystemTimeError> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
+    pub fn from_now() -> Result<Self, SystemTimeError> {
         let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)?;
         let epoch = now.as_secs();
         Ok(Self::new(epoch as i64, now.subsec_nanos()))
@@ -360,49 +353,43 @@ impl UnixTime {
         self.secs as f64 + (self.subsec_nanos as f64 / 1_000_000_000.0)
     }
 
-    pub fn as_secs(&self) -> i64 {
+    pub fn secs(&self) -> i64 {
         self.secs
     }
 
     #[cfg(feature = "chrono")]
-    pub fn chrono_date_time(&self) -> chrono::LocalResult<chrono::DateTime<chrono::Utc>> {
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
+    pub fn chrono_date_time(&self) -> LocalResult<DateTime<Utc>> {
         Utc.timestamp_opt(self.secs, self.subsec_nanos)
     }
 
     #[cfg(feature = "timelib")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "timelib")))]
     pub fn timelib_date_time(&self) -> Result<time::OffsetDateTime, time::error::ComponentRange> {
-        Ok(time::OffsetDateTime::from_unix_timestamp(self.as_secs())?
+        Ok(time::OffsetDateTime::from_unix_timestamp(self.secs())?
             + time::Duration::nanoseconds(self.subsec_nanos().into()))
     }
 
     // Calculate the difference in milliseconds between two UnixTimestamps
-    pub fn diff_in_millis(&self, other: &UnixTime) -> Option<i64> {
+    pub fn diff_in_millis(&self, other: &UnixTime) -> i64 {
-        let seconds_difference = self.secs.checked_sub(other.secs)?;
+        let seconds_difference = self.secs - other.secs;
         // Convert seconds difference to milliseconds
-        let milliseconds_difference = seconds_difference.checked_mul(1000)?;
+        let milliseconds_difference = seconds_difference * 1000;
 
         // Calculate the difference in subsecond milliseconds directly
         let subsecond_difference_nanos = self.subsec_nanos as i64 - other.subsec_nanos as i64;
 
         // Combine the differences
-        Some(milliseconds_difference + (subsecond_difference_nanos / 1_000_000))
+        milliseconds_difference + (subsecond_difference_nanos / 1_000_000)
     }
 }
 
-#[cfg(feature = "chrono")]
+impl From<DateTime<Utc>> for UnixTime {
-impl From<chrono::DateTime<chrono::Utc>> for UnixTime {
+    fn from(value: DateTime<Utc>) -> Self {
-    fn from(value: chrono::DateTime<chrono::Utc>) -> Self {
         Self::new(value.timestamp(), value.timestamp_subsec_nanos())
     }
 }
 
-#[cfg(feature = "timelib")]
-impl From<time::OffsetDateTime> for UnixTime {
-    fn from(value: time::OffsetDateTime) -> Self {
-        Self::new(value.unix_timestamp(), value.nanosecond())
-    }
-}
-
 impl PartialOrd for UnixTime {
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
         Some(self.cmp(other))
@@ -450,11 +437,11 @@ pub struct StampDiff {
 }
 
 impl Sub for UnixTime {
-    type Output = Option<StampDiff>;
+    type Output = StampDiff;
 
     fn sub(self, rhs: Self) -> Self::Output {
-        let difference = self.diff_in_millis(&rhs)?;
+        let difference = self.diff_in_millis(&rhs);
-        Some(if difference < 0 {
+        if difference < 0 {
             StampDiff {
                 positive_duration: false,
                 duration_absolute: Duration::from_millis(-difference as u64),
@@ -464,7 +451,7 @@ impl Sub for UnixTime {
                 positive_duration: true,
                 duration_absolute: Duration::from_millis(difference as u64),
             }
-        })
+        }
     }
 }
 
@@ -653,7 +640,7 @@ mod tests {
     fn test_addition() {
         let mut stamp0 = UnixTime::new_only_secs(1);
         stamp0 += Duration::from_secs(5);
-        assert_eq!(stamp0.as_secs(), 6);
+        assert_eq!(stamp0.secs(), 6);
         assert_eq!(stamp0.subsec_millis(), 0);
         let stamp1 = stamp0 + Duration::from_millis(500);
         assert_eq!(stamp1.secs, 6);
@@ -682,7 +669,7 @@ mod tests {
 
     #[test]
     fn test_from_now() {
-        let stamp_now = UnixTime::now().unwrap();
+        let stamp_now = UnixTime::from_now().unwrap();
         let dt_now = stamp_now.chrono_date_time().unwrap();
         assert!(dt_now.year() >= 2020);
     }
@@ -693,7 +680,7 @@ mod tests {
         let StampDiff {
             positive_duration,
             duration_absolute,
-        } = (stamp_later - UnixTime::new(1, 0)).expect("stamp diff error");
+        } = stamp_later - UnixTime::new(1, 0);
         assert!(positive_duration);
         assert_eq!(duration_absolute, Duration::from_secs(1));
     }
@@ -705,7 +692,7 @@ mod tests {
         let StampDiff {
             positive_duration,
             duration_absolute,
-        } = (stamp_later - stamp_earlier).expect("stamp diff error");
+        } = stamp_later - stamp_earlier;
         assert!(positive_duration);
         assert_eq!(duration_absolute, Duration::from_millis(1900));
     }
@@ -717,7 +704,7 @@ mod tests {
         let StampDiff {
             positive_duration,
             duration_absolute,
-        } = (stamp_earlier - stamp_later).expect("stamp diff error");
+        } = stamp_earlier - stamp_later;
         assert!(!positive_duration);
         assert_eq!(duration_absolute, Duration::from_millis(1900));
     }
@@ -752,13 +739,4 @@ mod tests {
         assert_eq!(timelib_dt.minute(), 0);
         assert_eq!(timelib_dt.second(), 0);
     }
-
-    #[test]
-    #[cfg(feature = "timelib")]
-    fn test_unix_stamp_from_timelib_datetime() {
-        let timelib_dt = time::OffsetDateTime::UNIX_EPOCH;
-        let unix_time = UnixTime::from(timelib_dt);
-        let timelib_converted_back = unix_time.timelib_date_time().unwrap();
-        assert_eq!(timelib_dt, timelib_converted_back);
-    }
 }

src/util.rs

@@ -77,6 +77,7 @@ pub trait UnsignedEnum {
     fn value(&self) -> u64;
 
     #[cfg(feature = "alloc")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "alloc")))]
     fn to_vec(&self) -> alloc::vec::Vec<u8> {
         let mut buf = alloc::vec![0; self.size()];
         self.write_to_be_bytes(&mut buf).unwrap();
@@ -131,7 +132,6 @@ impl Error for UnsignedByteFieldError {}
 /// Type erased variant.
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct UnsignedByteField {
     width: usize,
     value: u64,
@@ -221,7 +221,6 @@ impl UnsignedEnum for UnsignedByteField {
 
 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct GenericUnsignedByteField<TYPE: Copy + Into<u64>> {
     value: TYPE,
 }