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