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//! Example on how to read a 24C/24LC i2c eeprom with low power consumption.
//! The eeprom is read every 1 second, while ensuring lowest possible power while
//! sleeping between reads.
//!
//! Connect SDA to P0.03, SCL to P0.04
#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use core::mem;
use defmt::*;
use embassy::executor::Spawner;
use embassy::time::{Duration, Timer};
use embassy_nrf::twim::{self, Twim};
use embassy_nrf::{interrupt, Peripherals};
use defmt_rtt as _; // global logger
use panic_probe as _;
const ADDRESS: u8 = 0x50;
#[embassy::main]
async fn main(_spawner: Spawner, mut p: Peripherals) {
info!("Started!");
let mut irq = interrupt::take!(SPIM0_SPIS0_TWIM0_TWIS0_SPI0_TWI0);
loop {
info!("Initializing TWI...");
let config = twim::Config::default();
// Create the TWIM instance with borrowed singletons, so they're not consumed.
let mut twi = Twim::new(&mut p.TWISPI0, &mut irq, &mut p.P0_03, &mut p.P0_04, config);
info!("Reading...");
let mut buf = [0u8; 16];
unwrap!(twi.blocking_write_read(ADDRESS, &mut [0x00], &mut buf));
info!("Read: {=[u8]:x}", buf);
// Drop the TWIM instance. This disables the peripehral and deconfigures the pins.
// This clears the borrow on the singletons, so they can now be used again.
mem::drop(twi);
// Sleep for 1 second. The executor ensures the core sleeps with a WFE when it has nothing to do.
// During this sleep, the nRF chip should only use ~3uA
Timer::after(Duration::from_secs(1)).await;
}
}
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