Reading from the sensor

.cargo/config.toml

@@ -15,8 +15,6 @@ rustflags = [
     "link-arg=--nmagic",
     "-C",
     "link-arg=-Tlink.x",
-    # "-C",
-    # "link-arg=-Tdefmt.x",
     "-C",
     "target-cpu=cortex-m33",
 ]
@@ -24,13 +22,6 @@ rustflags = [
 runner = "picotool load -u -v -x -t elf"
 
 [target.riscv32imac-unknown-none-elf]
-rustflags = [
+rustflags = ["-C", "link-arg=--nmagic", "-C", "link-arg=-Trp235x_riscv.x"]
-    "-C",
-    "link-arg=--nmagic",
-    "-C",
-    "link-arg=-Trp235x_riscv.x",
-    # "-C",
-    # "link-arg=-Tdefmt.x",
-]
 
 runner = "picotool load -u -v -x -t elf"

.gitignore

@@ -1,2 +1,5 @@
 # Cargo
 target/
+
+# VSCode
+.vscode

Cargo.lock

@@ -211,6 +211,12 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "log"
+version = "0.4.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04cbf5b083de1c7e0222a7a51dbfdba1cbe1c6ab0b15e29fff3f6c077fd9cd9f"
+
 [[package]]
 name = "nb"
 version = "0.1.3"
@@ -246,12 +252,6 @@ dependencies = [
  "syn 1.0.109",
 ]
 
-[[package]]
-name = "panic-halt"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a513e167849a384b7f9b746e517604398518590a9142f4846a32e3c2a4de7b11"
-
 [[package]]
 name = "paste"
 version = "1.0.15"
@@ -262,10 +262,12 @@ checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 name = "pico-enviro-sensor"
 version = "0.1.0"
 dependencies = [
+ "critical-section",
  "embedded-hal 1.0.0",
  "fugit",
- "panic-halt",
  "rp235x-hal",
+ "rtt-target",
+ "scd4x",
 ]
 
 [[package]]
@@ -414,6 +416,17 @@ dependencies = [
  "vcell",
 ]
 
+[[package]]
+name = "rtt-target"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4235cd78091930e907d2a510adb0db1369e82668eafa338f109742fa0c83059d"
+dependencies = [
+ "critical-section",
+ "portable-atomic",
+ "ufmt-write",
+]
+
 [[package]]
 name = "rustc_version"
 version = "0.2.3"
@@ -423,6 +436,16 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "scd4x"
+version = "0.4.0"
+source = "git+https://github.com/twokilohertz/scd4x-rs.git?branch=conversion-fixes#07730523c51d6909530c000de271832125760385"
+dependencies = [
+ "embedded-hal 1.0.0",
+ "log",
+ "sensirion-i2c",
+]
+
 [[package]]
 name = "semver"
 version = "0.9.0"
@@ -438,6 +461,15 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 
+[[package]]
+name = "sensirion-i2c"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "640a03c95c176226cf159ae2727f7fe3245546022639d61459af46d2878aec06"
+dependencies = [
+ "embedded-hal 1.0.0",
+]
+
 [[package]]
 name = "sha2-const-stable"
 version = "0.1.0"
@@ -472,6 +504,12 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "ufmt-write"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e87a2ed6b42ec5e28cc3b94c09982969e9227600b2e3dcbc1db927a84c06bd69"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.17"

Cargo.toml

@@ -8,13 +8,17 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-embedded-hal = "1.0.0"
-fugit = "0.3.7"
-panic-halt = "1.0.0"
 rp235x-hal = { version = "0.2.0", features = [
     "critical-section-impl",
     "binary-info",
 ] }
+critical-section = "1.2.0"
+embedded-hal = "1.0.0"
+fugit = "0.3.7"
+scd4x = { git = "https://github.com/twokilohertz/scd4x-rs.git", branch = "conversion-fixes", features = [
+    "scd41",
+] }
+rtt-target = "0.6.1"
 
 # Super-optimised release build, maximum performance, minimal debuggability
 # Build with cargo build --profile dist

src/main.rs

@@ -3,17 +3,13 @@
 
 use embedded_hal::delay::DelayNs;
 use fugit::RateExtU32;
-use panic_halt as _; // Needed so its built & linked correctly
+use rtt_target::{rprintln, rtt_init_print};
-
-// Alias for our HAL crate
-use rp235x_hal as hal;
 
 // RP235x HAL
-use hal::uart::DataBits;
+use rp235x_hal as hal;
-use hal::uart::StopBits;
+
-use hal::uart::UartConfig;
+// Sensor
-use hal::uart::UartPeripheral;
+use scd4x::Scd4x;
-use hal::Clock;
 
 mod constants;
 
@@ -23,6 +19,9 @@ pub static IMAGE_DEF: hal::block::ImageDef = hal::block::ImageDef::secure_exe();
 
 #[hal::entry]
 fn main() -> ! {
+    rtt_init_print!();
+    rprintln!("Logging over RTT initialised");
+
     let mut peripherals = hal::pac::Peripherals::take().unwrap();
 
     let mut watchdog = hal::Watchdog::new(peripherals.WATCHDOG);
@@ -49,18 +48,73 @@ fn main() -> ! {
         &mut peripherals.RESETS,
     );
 
-    let uart0_pins = (pins.gpio0.into_function(), pins.gpio1.into_function());
+    rprintln!("Core RP2350 hardware initialisation successful");
 
-    let uart = UartPeripheral::new(peripherals.UART0, uart0_pins, &mut peripherals.RESETS)
+    // Initialise SCD41 sensor
-        .enable(
+    let i2c0 = hal::I2C::i2c0(
-            UartConfig::new(9600_u32.Hz(), DataBits::Eight, None, StopBits::One),
+        peripherals.I2C0,
-            clocks.peripheral_clock.freq(),
+        pins.gpio4.reconfigure(), // Pin 6 on Pico 2 (SDA)
-        )
+        pins.gpio5.reconfigure(), // Pin 7 on Pico 2 (SCL)
-        .unwrap();
+        400.kHz(),
+        &mut peripherals.RESETS,
+        &clocks.peripheral_clock,
+    );
+
+    timer.delay_ms(30); // Power-up delay
+    let mut scd41 = Scd4x::new(i2c0, timer);
+    scd41.wake_up();
+
+    match scd41.reinit() {
+        Ok(_) => rprintln!("Initialised SCD41"),
+        Err(error) => rprintln!("Failed to initialise SCD41: {:?}", error),
+    }
+    timer.delay_ms(30); // Soft reset delay
+
+    match scd41.serial_number() {
+        Ok(serial) => rprintln!("SCD41 serial number: {}", serial),
+        Err(error) => rprintln!("SCD41 did not respond to get_serial_number: {:?}", error),
+    }
+
+    match scd41.self_test_is_ok() {
+        Ok(ok) => {
+            if ok {
+                rprintln!("SCD41 reported successful self-test")
+            } else {
+                rprintln!("SCD41 reported unsuccessful self-test!")
+            }
+        }
+        Err(_) => rprintln!("SCD41 failed to perform self-test"),
+    }
+
+    match scd41.start_periodic_measurement() {
+        Ok(_) => rprintln!("Configured sensor to measure every 5 seconds"),
+        Err(error) => rprintln!("SCD41 start_periodic_measurement() failed: {:?}", error),
+    }
 
     loop {
-        uart.write_full_blocking(b"hello, world!\r\n");
+        timer.delay_ms(5010);
-        timer.delay_ms(500);
+        match scd41.measurement() {
+            Ok(data) => rprintln!(
+                "CO2: {}, temperature: {}, humidity: {}",
+                data.co2,
+                data.temperature,
+                data.humidity
+            ),
+            Err(error) => rprintln!("SCD41 get_measurement() failed: {:?}", error),
+        }
+    }
+
+    // loop {
+    //     hal::arch::wfi();
+    // }
+}
+
+#[inline(never)]
+#[panic_handler]
+fn panic(info: &core::panic::PanicInfo) -> ! {
+    rprintln!("Panicked! {}", info);
+    loop {
+        hal::arch::nop()
     }
 }