diff --git a/Cargo.toml b/Cargo.toml
index c82507f..d01ea30 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -48,6 +48,10 @@ optional = true
 version = "0.2"
 default-features = false
 
+[dependencies.defmt]
+version = "0.3"
+optional = true
+
 [dev-dependencies]
 postcard = "1"
 chrono = "0.4"
@@ -59,6 +63,7 @@ serde = ["dep:serde", "chrono/serde"]
 alloc = ["postcard/alloc", "chrono/alloc"]
 chrono = ["dep:chrono"]
 timelib = ["dep:time"]
+defmt = []
 
 [package.metadata.docs.rs]
 all-features = true
diff --git a/src/ecss/mod.rs b/src/ecss/mod.rs
index 8aab2a1..e078cdb 100644
--- a/src/ecss/mod.rs
+++ b/src/ecss/mod.rs
@@ -150,6 +150,7 @@ 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),