Added I2C / Temperature Sensor example

- Example using the on-board ADT75 I2C temperature sensor
- Bump HAL version to use new I2C library

Cargo.toml

@@ -16,7 +16,7 @@ cortex-m-rt = "0.7.0"
 embedded-hal = "0.2.6"
 
 [dependencies.va108xx-hal]
-version = "0.2.1"
+version = "0.2.2"
 features = ["rt"]
 
 [dev-dependencies]

examples/blinky-button-irq.rs

@@ -2,7 +2,7 @@
 #![no_main]
 #![no_std]
 
-use core::cell::{Cell, RefCell};
+use core::cell::RefCell;
 
 use cortex_m::interrupt::Mutex;
 use cortex_m_rt::entry;
@@ -14,13 +14,12 @@ use va108xx_hal::{
     pac::{self, interrupt},
     prelude::*,
     time::Hertz,
-    timer::set_up_ms_timer,
+    timer::{default_ms_irq_handler, set_up_ms_timer},
 };
 use vorago_reb1::button::Button;
 use vorago_reb1::leds::Leds;
 
 static LEDS: Mutex<RefCell<Option<Leds>>> = Mutex::new(RefCell::new(None));
-static MS_COUNTER: Mutex<Cell<u32>> = Mutex::new(Cell::new(0));
 static BUTTON: Mutex<RefCell<Option<Button>>> = Mutex::new(RefCell::new(None));
 
 #[derive(Debug, PartialEq)]
@@ -95,11 +94,7 @@ fn unmask_irqs() {
 
 #[interrupt]
 fn OC0() {
-    cortex_m::interrupt::free(|cs| {
+    default_ms_irq_handler();
-        let mut ms = MS_COUNTER.borrow(cs).get();
-        ms += 1;
-        MS_COUNTER.borrow(cs).set(ms);
-    });
 }
 
 #[interrupt]

examples/temp-sensor.rs

@@ -0,0 +1,77 @@
+#![no_main]
+#![no_std]
+use cortex_m_rt::entry;
+use embedded_hal::blocking::i2c::SevenBitAddress;
+use panic_rtt_target as _;
+use rtt_target::{rprintln, rtt_init_print};
+use va108xx_hal::{
+    i2c::{I2cMaster, I2cSpeed, MasterConfig},
+    pac::{self, interrupt, I2CA},
+    prelude::*,
+    timer::{default_ms_irq_handler, set_up_ms_timer, Delay},
+};
+
+#[allow(dead_code)]
+enum RegAddresses {
+    Temperature = 0x00,
+    Configuration = 0x01,
+    THystSetpoint = 0x02,
+    TOsSetPoint = 0x03,
+    OneShot = 0x04,
+}
+
+const ADT75_I2C_ADDR: u8 = 0b1001000;
+
+#[entry]
+fn main() -> ! {
+    rtt_init_print!();
+    rprintln!("-- Vorago Temperature Sensor and I2C Example --");
+    let mut dp = pac::Peripherals::take().unwrap();
+    let tim0 = set_up_ms_timer(
+        &mut dp.SYSCONFIG,
+        &mut dp.IRQSEL,
+        50.mhz().into(),
+        dp.TIM0,
+        interrupt::OC0,
+    );
+    let mut delay = Delay::new(tim0);
+    unsafe {
+        cortex_m::peripheral::NVIC::unmask(pac::Interrupt::OC0);
+    }
+
+    let ms_cfg = MasterConfig::default();
+    let mut i2ca: I2cMaster<I2CA, SevenBitAddress> = I2cMaster::i2ca(
+        dp.I2CA,
+        ms_cfg,
+        50.mhz(),
+        I2cSpeed::Regular100khz,
+        Some(&mut dp.SYSCONFIG),
+    );
+
+    let mut cmd: [u8; 4] = [0; 4];
+    cmd[0] = RegAddresses::Temperature as u8;
+    let mut reply: [u8; 4] = [0; 4];
+    i2ca.write(ADT75_I2C_ADDR, &cmd[0..1])
+        .expect("I2C send transfer failed");
+    loop {
+        i2ca.read(ADT75_I2C_ADDR, &mut reply[0..2])
+            .expect("I2C read transfer failed");
+        let adc_code = (((reply[0] as u16) << 8) | reply[1] as u16) >> 4;
+        let temp_celcius: f32;
+        if ((adc_code >> 11) & 0x01) == 0 {
+            // Sign bit not set, positiv value
+            // Divide ADC code by 16 according to datasheet
+            temp_celcius = adc_code as f32 / 16.0;
+        } else {
+            // Calculation for negative values, assuming all 12 bits are used
+            temp_celcius = (adc_code - 4096) as f32 / 16.0;
+        }
+        rprintln!("Temperature in Celcius: {}", temp_celcius);
+        delay.delay_ms(500);
+    }
+}
+
+#[interrupt]
+fn OC0() {
+    default_ms_irq_handler();
+}