diff --git a/src/bin/temp_rh_measurement.rs b/src/bin/temp_rh_measurement.rs index 03b9482..296cb0a 100644 --- a/src/bin/temp_rh_measurement.rs +++ b/src/bin/temp_rh_measurement.rs @@ -6,40 +6,113 @@ use nrf_softdevice::{raw, Softdevice}; use defmt::*; use embassy_executor::Spawner; -use embassy_nrf::twim::{self, Twim}; -use embassy_nrf::{bind_interrupts, peripherals}; +use embassy_nrf::gpio::Pin as GpioPin; +use embassy_nrf::interrupt; +use embassy_nrf::twim::{self, Instance as TwimInstance, InterruptHandler, Twim}; +use embassy_nrf::{bind_interrupts, peripherals, Peripheral}; use {defmt_rtt as _, panic_probe as _}; -const ADDRESS: u8 = 0x44; +struct I2cDriver<'a, T: TwimInstance> { + address: u8, + twim: Twim<'a, T>, +} -bind_interrupts!(struct Irqs { - TWIM0_TWIS0_TWI0 => twim::InterruptHandler; -}); +trait Driver { + /// The msg being mutable ensures that it doesn't have to be copied into RAM for DMA access, as + /// it is already there + fn write(&mut self, msg: &mut [u8]); + fn read(&mut self, buffer: &mut [u8]); +} -#[embassy_executor::main] -async fn main(_spawner: Spawner) { - let p = embassy_nrf::init(Default::default()); +impl<'a, T: TwimInstance> Driver for I2cDriver<'a, T> { + fn write(&mut self, msg: &mut [u8]) { + unwrap!(self.twim.blocking_write(self.address, &mut *msg)); + } - info!("Initializing TWI..."); + fn read(&mut self, buffer: &mut [u8]) { + unwrap!(self.twim.blocking_read(self.address, &mut *buffer)); + } +} - let config = twim::Config::default(); - let mut twi = Twim::new(p.TWI0, Irqs, p.P0_14, p.P0_13, config); +impl<'a, T: TwimInstance> I2cDriver<'a, T> { + fn new( + address: u8, + peripheral: impl Peripheral

+ 'a, + sda: impl Peripheral

+ 'a, + scl: impl Peripheral

+ 'a, + _irq: impl interrupt::typelevel::Binding> + 'a, + ) -> Self { + let config = twim::Config::default(); + let twim = Twim::new(peripheral, _irq, sda, scl, config); - loop { - unwrap!(twi.blocking_write(ADDRESS, &mut [0xFD])); + Self { address, twim } + } +} - Timer::after_millis(10).await; +struct MockI2cDriver; +impl Driver for MockI2cDriver { + fn write(&mut self, _: &mut [u8]) {} + + fn read(&mut self, buffer: &mut [u8]) { + buffer[0] = 127; + buffer[1] = 128; + buffer[2] = 129; + buffer[3] = 130; + buffer[4] = 131; + buffer[5] = 132; + } +} + +impl MockI2cDriver { + fn new(_: u8) -> Self { + Self {} + } +} + +struct TempHumiditySensor { + driver: T, +} + +// TODO: Implement CRC checks +impl TempHumiditySensor { + fn new(driver: T) -> Self { + Self { driver } + } + + /// The procedure for reading out the temperature and humidity and converting them to floats is + /// detailed in the datasheet of the SHT41-AD1B-R2. + async fn read_temp_and_humidity(&mut self) -> (f32, f32) { let mut buf = [0u8; 6]; - unwrap!(twi.blocking_read(ADDRESS, &mut buf)); + + self.driver.write(&mut [0xFD]); + Timer::after_millis(10).await; + self.driver.read(&mut buf); let temp_int = u16::from_be_bytes([buf[0], buf[1]]); let temp_float: f32 = -45f32 + 175f32 * (temp_int as f32 / (2u32.pow(16) - 1) as f32); let rh_int = u16::from_be_bytes([buf[3], buf[4]]); let rh_float: f32 = -6f32 + 125f32 * (rh_int as f32 / (2u32.pow(16) - 1) as f32); - println!("{}\t{}", temp_float, rh_float); + return (temp_float, rh_float); + } +} + +bind_interrupts!(struct Irqs { + SPIM0_SPIS0_TWIM0_TWIS0_SPI0_TWI0 => twim::InterruptHandler; +}); + +#[embassy_executor::main] +async fn main(_spawner: Spawner) { + let p = embassy_nrf::init(Default::default()); + + let driver = I2cDriver::new(0x44, p.TWISPI0, p.P0_14, p.P0_13, Irqs); + let mut sensor = TempHumiditySensor::new(driver); + + loop { + let (temp, humidity) = sensor.read_temp_and_humidity().await; + println!("{} °C\t{} %", temp, humidity); Timer::after_millis(50).await; } }