embassy/examples/stm32f4/src/bin/i2c_async.rs
2023-11-24 23:55:46 +01:00

63 lines
1.9 KiB
Rust

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
// Example originally designed for stm32f411ceu6 reading an A1454 hall effect sensor on I2C1
// DMA peripherals changed to compile for stm32f429zi, for the CI.
use defmt::*;
use embassy_executor::Spawner;
use embassy_stm32::i2c::I2c;
use embassy_stm32::time::Hertz;
use embassy_stm32::{bind_interrupts, i2c, peripherals};
use {defmt_rtt as _, panic_probe as _};
const ADDRESS: u8 = 96;
bind_interrupts!(struct Irqs {
I2C1_EV => i2c::EventInterruptHandler<peripherals::I2C1>;
I2C1_ER => i2c::ErrorInterruptHandler<peripherals::I2C1>;
});
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
info!("Hello world!");
let p = embassy_stm32::init(Default::default());
let mut i2c = I2c::new(
p.I2C1,
p.PB8,
p.PB7,
Irqs,
p.DMA1_CH6,
p.DMA1_CH0,
Hertz(100_000),
Default::default(),
);
loop {
let a1454_read_sensor_command = [0x1F];
let mut sensor_data_buffer: [u8; 4] = [0, 0, 0, 0];
match i2c
.write_read(ADDRESS, &a1454_read_sensor_command, &mut sensor_data_buffer)
.await
{
Ok(()) => {
// Convert 12-bit signed integer into 16-bit signed integer.
// Is the 12 bit number negative?
if (sensor_data_buffer[2] & 0b00001000) == 0b0001000 {
sensor_data_buffer[2] = sensor_data_buffer[2] | 0b11110000;
}
let mut sensor_value_raw: u16 = sensor_data_buffer[3].into();
sensor_value_raw |= (sensor_data_buffer[2] as u16) << 8;
let sensor_value: u16 = sensor_value_raw.into();
let sensor_value = sensor_value as i16;
info!("Data: {}", sensor_value);
}
Err(e) => error!("I2C Error during read: {:?}", e),
}
}
}