Add new driver implementations and workspace updates

drivers/0x0d_timer_rust/src/board.rs

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+//! @file board.rs
+//! @brief Board-level HAL helpers for the timer driver
+//! @author Kevin Thomas
+//! @date 2025
+//!
+//! MIT License
+//!
+//! Copyright (c) 2025 Kevin Thomas
+//!
+//! Permission is hereby granted, free of charge, to any person obtaining a copy
+//! of this software and associated documentation files (the "Software"), to deal
+//! in the Software without restriction, including without limitation the rights
+//! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//! copies of the Software, and to permit persons to whom the Software is
+//! furnished to do so, subject to the following conditions:
+//!
+//! The above copyright notice and this permission notice shall be included in
+//! all copies or substantial portions of the Software.
+//!
+//! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//! SOFTWARE.
+
+// Timer driver pure-logic functions and constants
+use crate::timer_driver;
+// Rate extension trait for .Hz() baud rate construction
+use fugit::RateExtU32;
+// Clock trait for accessing system clock frequency
+use hal::Clock;
+// GPIO pin types and function selectors
+use hal::gpio::{FunctionNull, FunctionUart, Pin, PullDown, PullNone};
+// UART configuration and peripheral types
+use hal::uart::{DataBits, Enabled, StopBits, UartConfig, UartPeripheral};
+
+// Alias our HAL crate
+#[cfg(rp2350)]
+use rp235x_hal as hal;
+#[cfg(rp2040)]
+use rp2040_hal as hal;
+
+/// Timer device type for the HAL timer peripheral.
+#[cfg(rp2350)]
+pub(crate) type HalTimer = hal::Timer<hal::timer::CopyableTimer0>;
+/// Timer type alias for RP2040 (non-generic).
+#[cfg(rp2040)]
+pub(crate) type HalTimer = hal::Timer;
+
+/// External crystal frequency in Hz (12 MHz).
+pub(crate) const XTAL_FREQ_HZ: u32 = 12_000_000u32;
+
+/// UART baud rate in bits per second.
+pub(crate) const UART_BAUD: u32 = 115_200;
+
+/// Type alias for the configured TX pin (GPIO 0, UART function, no pull).
+pub(crate) type TxPin = Pin<hal::gpio::bank0::Gpio0, FunctionUart, PullNone>;
+
+/// Type alias for the configured RX pin (GPIO 1, UART function, no pull).
+pub(crate) type RxPin = Pin<hal::gpio::bank0::Gpio1, FunctionUart, PullNone>;
+
+/// Type alias for the default TX pin state from `Pins::new()`.
+pub(crate) type TxPinDefault = Pin<hal::gpio::bank0::Gpio0, FunctionNull, PullDown>;
+
+/// Type alias for the default RX pin state from `Pins::new()`.
+pub(crate) type RxPinDefault = Pin<hal::gpio::bank0::Gpio1, FunctionNull, PullDown>;
+
+/// Type alias for the fully-enabled UART0 peripheral with TX/RX pins.
+pub(crate) type EnabledUart = UartPeripheral<Enabled, hal::pac::UART0, (TxPin, RxPin)>;
+
+/// Initialise system clocks and PLLs from the external 12 MHz crystal.
+///
+/// # Arguments
+///
+/// * `xosc` - XOSC peripheral singleton.
+/// * `clocks` - CLOCKS peripheral singleton.
+/// * `pll_sys` - PLL_SYS peripheral singleton.
+/// * `pll_usb` - PLL_USB peripheral singleton.
+/// * `resets` - Mutable reference to the RESETS peripheral.
+/// * `watchdog` - Mutable reference to the watchdog timer.
+///
+/// # Returns
+///
+/// Configured clocks manager.
+///
+/// # Panics
+///
+/// Panics if clock initialisation fails.
+pub(crate) fn init_clocks(
+    xosc: hal::pac::XOSC,
+    clocks: hal::pac::CLOCKS,
+    pll_sys: hal::pac::PLL_SYS,
+    pll_usb: hal::pac::PLL_USB,
+    resets: &mut hal::pac::RESETS,
+    watchdog: &mut hal::Watchdog,
+) -> hal::clocks::ClocksManager {
+    hal::clocks::init_clocks_and_plls(
+        XTAL_FREQ_HZ, xosc, clocks, pll_sys, pll_usb, resets, watchdog,
+    )
+    .unwrap()
+}
+
+/// Unlock the GPIO bank and return the pin set.
+///
+/// # Arguments
+///
+/// * `io_bank0` - IO_BANK0 peripheral singleton.
+/// * `pads_bank0` - PADS_BANK0 peripheral singleton.
+/// * `sio` - SIO peripheral singleton.
+/// * `resets` - Mutable reference to the RESETS peripheral.
+///
+/// # Returns
+///
+/// GPIO pin set for the entire bank.
+pub(crate) fn init_pins(
+    io_bank0: hal::pac::IO_BANK0,
+    pads_bank0: hal::pac::PADS_BANK0,
+    sio: hal::pac::SIO,
+    resets: &mut hal::pac::RESETS,
+) -> hal::gpio::Pins {
+    let sio = hal::Sio::new(sio);
+    hal::gpio::Pins::new(io_bank0, pads_bank0, sio.gpio_bank0, resets)
+}
+
+/// Initialise UART0 for serial output (stdio equivalent).
+///
+/// # Arguments
+///
+/// * `uart0` - PAC UART0 peripheral singleton.
+/// * `tx_pin` - GPIO pin to use as UART0 TX (GPIO 0).
+/// * `rx_pin` - GPIO pin to use as UART0 RX (GPIO 1).
+/// * `resets` - Mutable reference to the RESETS peripheral.
+/// * `clocks` - Reference to the initialised clock configuration.
+///
+/// # Returns
+///
+/// Enabled UART0 peripheral ready for blocking writes.
+///
+/// # Panics
+///
+/// Panics if the HAL cannot achieve the requested baud rate.
+pub(crate) fn init_uart(
+    uart0: hal::pac::UART0,
+    tx_pin: TxPinDefault,
+    rx_pin: RxPinDefault,
+    resets: &mut hal::pac::RESETS,
+    clocks: &hal::clocks::ClocksManager,
+) -> EnabledUart {
+    let pins = (
+        tx_pin.reconfigure::<FunctionUart, PullNone>(),
+        rx_pin.reconfigure::<FunctionUart, PullNone>(),
+    );
+    let cfg = UartConfig::new(UART_BAUD.Hz(), DataBits::Eight, None, StopBits::One);
+    UartPeripheral::new(uart0, pins, resets)
+        .enable(cfg, clocks.peripheral_clock.freq())
+        .unwrap()
+}
+
+/// Create a blocking delay timer from the ARM SysTick peripheral.
+///
+/// # Arguments
+///
+/// * `clocks` - Reference to the initialised clock configuration.
+///
+/// # Returns
+///
+/// Blocking delay provider.
+///
+/// # Panics
+///
+/// Panics if the cortex-m core peripherals have already been taken.
+pub(crate) fn init_delay(clocks: &hal::clocks::ClocksManager) -> cortex_m::delay::Delay {
+    let core = cortex_m::Peripherals::take().unwrap();
+    cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().to_Hz())
+}
+
+/// Run the repeating timer heartbeat loop.
+///
+/// Polls the HAL timer, and each time the configured period elapses,
+/// fires the driver state callback and prints the heartbeat message
+/// over UART. This mirrors the C demo's `_heartbeat_callback` being
+/// invoked by the Pico SDK repeating timer.
+///
+/// # Arguments
+///
+/// * `uart` - Reference to the enabled UART peripheral for serial output.
+/// * `timer` - Reference to the HAL timer for microsecond measurement.
+/// * `delay` - Mutable reference to the blocking delay provider.
+/// * `state` - Mutable reference to the timer driver state.
+pub(crate) fn heartbeat_loop(
+    uart: &EnabledUart,
+    timer: &HalTimer,
+    delay: &mut cortex_m::delay::Delay,
+    state: &mut timer_driver::TimerDriverState,
+) -> ! {
+    let mut last_us = timer.get_counter().ticks() as u32;
+    let period_us = state.period_ms() as u64 * 1_000;
+    loop {
+        let now_us = timer.get_counter().ticks() as u32;
+        let elapsed = now_us.wrapping_sub(last_us) as u64;
+        if elapsed >= period_us {
+            last_us = now_us;
+            if state.on_fire() {
+                let mut buf = [0u8; 32];
+                let n = timer_driver::format_heartbeat(&mut buf);
+                uart.write_full_blocking(&buf[..n]);
+            }
+        }
+        delay.delay_us(100);
+    }
+}
+
+// End of file

drivers/0x0d_timer_rust/src/lib.rs

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+//! @file lib.rs
+//! @brief Library root for the timer driver crate
+//! @author Kevin Thomas
+//! @date 2025
+
+#![no_std]
+
+// Timer driver module
+pub mod timer_driver;

drivers/0x0d_timer_rust/src/main.rs

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+//! @file main.rs
+//! @brief Repeating timer demo using timer_driver.rs
+//! @author Kevin Thomas
+//! @date 2025
+//!
+//! MIT License
+//!
+//! Copyright (c) 2025 Kevin Thomas
+//!
+//! Permission is hereby granted, free of charge, to any person obtaining a copy
+//! of this software and associated documentation files (the "Software"), to deal
+//! in the Software without restriction, including without limitation the rights
+//! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//! copies of the Software, and to permit persons to whom the Software is
+//! furnished to do so, subject to the following conditions:
+//!
+//! The above copyright notice and this permission notice shall be included in
+//! all copies or substantial portions of the Software.
+//!
+//! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//! SOFTWARE.
+//!
+//! -----------------------------------------------------------------------------
+//!
+//! Demonstrates repeating timer callbacks using the timer driver
+//! (timer_driver.rs). A one-second heartbeat timer prints a message
+//! over UART to confirm the timer is firing.
+//!
+//! Wiring:
+//!   No external wiring required
+
+#![no_std]
+#![no_main]
+
+// Board-level helpers: constants, type aliases, and init functions
+mod board;
+// Timer driver module — suppress warnings for unused public API functions
+#[allow(dead_code)]
+mod timer_driver;
+
+// Debugging output over RTT
+use defmt_rtt as _;
+// Panic handler for RISC-V targets
+#[cfg(target_arch = "riscv32")]
+use panic_halt as _;
+// Panic handler for ARM targets
+#[cfg(target_arch = "arm")]
+use panic_probe as _;
+
+// HAL entry-point macro
+use hal::entry;
+
+// Alias our HAL crate
+#[cfg(rp2350)]
+use rp235x_hal as hal;
+#[cfg(rp2040)]
+use rp2040_hal as hal;
+
+// Second-stage boot loader for RP2040
+#[unsafe(link_section = ".boot2")]
+#[used]
+#[cfg(rp2040)]
+pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
+
+// Boot metadata for the RP2350 Boot ROM
+#[unsafe(link_section = ".start_block")]
+#[used]
+#[cfg(rp2350)]
+pub static IMAGE_DEF: hal::block::ImageDef = hal::block::ImageDef::secure_exe();
+
+/// Application entry point for the repeating timer demo.
+#[entry]
+fn main() -> ! {
+    let mut pac = hal::pac::Peripherals::take().unwrap();
+    let clocks = board::init_clocks(
+        pac.XOSC, pac.CLOCKS, pac.PLL_SYS, pac.PLL_USB, &mut pac.RESETS,
+        &mut hal::Watchdog::new(pac.WATCHDOG),
+    );
+    let pins = board::init_pins(pac.IO_BANK0, pac.PADS_BANK0, pac.SIO, &mut pac.RESETS);
+    let uart = board::init_uart(pac.UART0, pins.gpio0, pins.gpio1, &mut pac.RESETS, &clocks);
+    let mut delay = board::init_delay(&clocks);
+    #[cfg(rp2350)]
+    let timer = hal::Timer::new_timer0(pac.TIMER0, &mut pac.RESETS, &clocks);
+    #[cfg(rp2040)]
+    let timer = hal::Timer::new(pac.TIMER, &mut pac.RESETS);
+    let mut state = timer_driver::TimerDriverState::new();
+    state.start(timer_driver::DEFAULT_PERIOD_MS);
+    let mut buf = [0u8; 64];
+    let n = timer_driver::format_started(&mut buf, timer_driver::DEFAULT_PERIOD_MS);
+    uart.write_full_blocking(&buf[..n]);
+    board::heartbeat_loop(&uart, &timer, &mut delay, &mut state);
+}
+
+// Picotool binary info metadata
+#[unsafe(link_section = ".bi_entries")]
+#[used]
+pub static PICOTOOL_ENTRIES: [hal::binary_info::EntryAddr; 5] = [
+    hal::binary_info::rp_cargo_bin_name!(),
+    hal::binary_info::rp_cargo_version!(),
+    hal::binary_info::rp_program_description!(c"Repeating Timer Demo"),
+    hal::binary_info::rp_cargo_homepage_url!(),
+    hal::binary_info::rp_program_build_attribute!(),
+];
+
+// End of file

drivers/0x0d_timer_rust/src/timer_driver.rs

@@ -0,0 +1,311 @@
+//! @file timer_driver.rs
+//! @brief Implementation of the repeating timer driver
+//! @author Kevin Thomas
+//! @date 2025
+//!
+//! MIT License
+//!
+//! Copyright (c) 2025 Kevin Thomas
+//!
+//! Permission is hereby granted, free of charge, to any person obtaining a copy
+//! of this software and associated documentation files (the "Software"), to deal
+//! in the Software without restriction, including without limitation the rights
+//! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//! copies of the Software, and to permit persons to whom the Software is
+//! furnished to do so, subject to the following conditions:
+//!
+//! The above copyright notice and this permission notice shall be included in
+//! all copies or substantial portions of the Software.
+//!
+//! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//! SOFTWARE.
+
+/// Default heartbeat message printed by the timer callback.
+pub const HEARTBEAT_MSG: &[u8] = b"Timer heartbeat\r\n";
+
+/// Default timer period in milliseconds.
+pub const DEFAULT_PERIOD_MS: u32 = 1_000;
+
+/// Timer driver state tracking whether the repeating timer is active.
+///
+/// Mirrors the C driver's `g_timer_active` / `g_user_callback` globals
+/// as a structured state machine testable on the host.
+pub struct TimerDriverState {
+    /// Whether the repeating timer is currently active.
+    active: bool,
+    /// Configured period in milliseconds.
+    period_ms: u32,
+    /// Number of times the callback has fired.
+    fire_count: u32,
+}
+
+impl TimerDriverState {
+    /// Create a new idle timer driver state.
+    ///
+    /// # Returns
+    ///
+    /// A `TimerDriverState` in the inactive state with zero fire count.
+    pub fn new() -> Self {
+        Self {
+            active: false,
+            period_ms: 0,
+            fire_count: 0,
+        }
+    }
+
+    /// Start the repeating timer with the given period.
+    ///
+    /// If the timer is already active it is first cancelled, matching
+    /// the C driver's `timer_driver_start()` behaviour.
+    ///
+    /// # Arguments
+    ///
+    /// * `period_ms` - Interval between callbacks in milliseconds.
+    pub fn start(&mut self, period_ms: u32) {
+        if self.active {
+            self.cancel();
+        }
+        self.period_ms = period_ms;
+        self.active = true;
+    }
+
+    /// Cancel the active repeating timer.
+    ///
+    /// Safe to call even if the timer is already inactive, matching
+    /// the C driver's `timer_driver_cancel()` behaviour.
+    pub fn cancel(&mut self) {
+        self.active = false;
+    }
+
+    /// Return whether the timer is currently active.
+    ///
+    /// # Returns
+    ///
+    /// `true` if a repeating timer is running, `false` otherwise.
+    pub fn is_active(&self) -> bool {
+        self.active
+    }
+
+    /// Return the configured timer period in milliseconds.
+    ///
+    /// # Returns
+    ///
+    /// The period set by the most recent `start()` call.
+    pub fn period_ms(&self) -> u32 {
+        self.period_ms
+    }
+
+    /// Return the total number of times the callback has fired.
+    ///
+    /// # Returns
+    ///
+    /// Cumulative fire count since construction.
+    pub fn fire_count(&self) -> u32 {
+        self.fire_count
+    }
+
+    /// Record that the callback has fired once.
+    ///
+    /// Called by the board-level shim each time the hardware alarm
+    /// triggers. Returns `true` to keep the timer repeating (matching
+    /// the C `_heartbeat_callback` return value).
+    ///
+    /// # Returns
+    ///
+    /// `true` if the timer should continue repeating.
+    pub fn on_fire(&mut self) -> bool {
+        if !self.active {
+            return false;
+        }
+        self.fire_count += 1;
+        true
+    }
+}
+
+/// Format the heartbeat message into a caller-supplied buffer.
+///
+/// Writes the fixed `HEARTBEAT_MSG` bytes and returns the number
+/// of bytes written.
+///
+/// # Arguments
+///
+/// * `buf` - Destination buffer (must be at least `HEARTBEAT_MSG.len()` bytes).
+///
+/// # Returns
+///
+/// Number of bytes written to `buf`.
+pub fn format_heartbeat(buf: &mut [u8]) -> usize {
+    let len = HEARTBEAT_MSG.len();
+    buf[..len].copy_from_slice(HEARTBEAT_MSG);
+    len
+}
+
+/// Format a timer-started banner message.
+///
+/// Writes "Repeating timer started (XXXX ms)\r\n" into `buf` and
+/// returns the number of bytes written.
+///
+/// # Arguments
+///
+/// * `buf` - Destination buffer (must be at least 40 bytes).
+/// * `period_ms` - Timer period to include in the message.
+///
+/// # Returns
+///
+/// Number of bytes written to `buf`.
+pub fn format_started(buf: &mut [u8], period_ms: u32) -> usize {
+    let prefix = b"Repeating timer started (";
+    let mut pos = prefix.len();
+    buf[..pos].copy_from_slice(prefix);
+    pos += format_u32(&mut buf[pos..], period_ms);
+    let suffix = b" ms)\r\n";
+    buf[pos..pos + suffix.len()].copy_from_slice(suffix);
+    pos + suffix.len()
+}
+
+/// Format an unsigned 32-bit integer as decimal ASCII.
+///
+/// # Arguments
+///
+/// * `buf` - Destination buffer.
+/// * `value` - Value to format.
+///
+/// # Returns
+///
+/// Number of ASCII digits written.
+fn format_u32(buf: &mut [u8], value: u32) -> usize {
+    if value == 0 {
+        buf[0] = b'0';
+        return 1;
+    }
+    let mut tmp = [0u8; 10];
+    let mut n = 0usize;
+    let mut v = value;
+    while v > 0 {
+        tmp[n] = b'0' + (v % 10) as u8;
+        v /= 10;
+        n += 1;
+    }
+    for i in 0..n {
+        buf[i] = tmp[n - 1 - i];
+    }
+    n
+}
+
+#[cfg(test)]
+mod tests {
+    // Import all parent module items
+    use super::*;
+
+    #[test]
+    fn new_state_is_inactive() {
+        let state = TimerDriverState::new();
+        assert!(!state.is_active());
+        assert_eq!(state.period_ms(), 0);
+        assert_eq!(state.fire_count(), 0);
+    }
+
+    #[test]
+    fn start_activates_timer() {
+        let mut state = TimerDriverState::new();
+        state.start(1_000);
+        assert!(state.is_active());
+        assert_eq!(state.period_ms(), 1_000);
+    }
+
+    #[test]
+    fn cancel_deactivates_timer() {
+        let mut state = TimerDriverState::new();
+        state.start(1_000);
+        state.cancel();
+        assert!(!state.is_active());
+    }
+
+    #[test]
+    fn cancel_when_inactive_is_safe() {
+        let mut state = TimerDriverState::new();
+        state.cancel();
+        assert!(!state.is_active());
+    }
+
+    #[test]
+    fn start_while_active_cancels_and_restarts() {
+        let mut state = TimerDriverState::new();
+        state.start(500);
+        state.start(2_000);
+        assert!(state.is_active());
+        assert_eq!(state.period_ms(), 2_000);
+    }
+
+    #[test]
+    fn on_fire_increments_count() {
+        let mut state = TimerDriverState::new();
+        state.start(1_000);
+        assert!(state.on_fire());
+        assert_eq!(state.fire_count(), 1);
+        assert!(state.on_fire());
+        assert_eq!(state.fire_count(), 2);
+    }
+
+    #[test]
+    fn on_fire_returns_false_when_inactive() {
+        let mut state = TimerDriverState::new();
+        assert!(!state.on_fire());
+        assert_eq!(state.fire_count(), 0);
+    }
+
+    #[test]
+    fn on_fire_after_cancel_returns_false() {
+        let mut state = TimerDriverState::new();
+        state.start(1_000);
+        assert!(state.on_fire());
+        state.cancel();
+        assert!(!state.on_fire());
+        assert_eq!(state.fire_count(), 1);
+    }
+
+    #[test]
+    fn format_heartbeat_matches_c_output() {
+        let mut buf = [0u8; 32];
+        let n = format_heartbeat(&mut buf);
+        assert_eq!(&buf[..n], b"Timer heartbeat\r\n");
+    }
+
+    #[test]
+    fn format_started_1000ms() {
+        let mut buf = [0u8; 48];
+        let n = format_started(&mut buf, 1_000);
+        assert_eq!(&buf[..n], b"Repeating timer started (1000 ms)\r\n");
+    }
+
+    #[test]
+    fn format_started_single_digit() {
+        let mut buf = [0u8; 48];
+        let n = format_started(&mut buf, 5);
+        assert_eq!(&buf[..n], b"Repeating timer started (5 ms)\r\n");
+    }
+
+    #[test]
+    fn format_u32_zero() {
+        let mut buf = [0u8; 10];
+        let n = format_u32(&mut buf, 0);
+        assert_eq!(&buf[..n], b"0");
+    }
+
+    #[test]
+    fn format_u32_large_value() {
+        let mut buf = [0u8; 10];
+        let n = format_u32(&mut buf, 123456);
+        assert_eq!(&buf[..n], b"123456");
+    }
+
+    #[test]
+    fn default_period_matches_c_demo() {
+        assert_eq!(DEFAULT_PERIOD_MS, 1_000);
+    }
+}