diff --git a/embassy-nrf-examples/src/bin/twim.rs b/embassy-nrf-examples/src/bin/twim.rs new file mode 100644 index 000000000..537cea160 --- /dev/null +++ b/embassy-nrf-examples/src/bin/twim.rs @@ -0,0 +1,35 @@ +//! Example on how to read a 24C/24LC i2c eeprom. +//! +//! Connect SDA to P0.03, SCL to P0.04 + +#![no_std] +#![no_main] +#![feature(min_type_alias_impl_trait)] +#![feature(impl_trait_in_bindings)] +#![feature(type_alias_impl_trait)] +#![allow(incomplete_features)] + +#[path = "../example_common.rs"] +mod example_common; + +use defmt::{panic, *}; +use embassy::executor::Spawner; +use embassy_nrf::twim::{self, Twim}; +use embassy_nrf::{interrupt, Peripherals}; + +const ADDRESS: u8 = 0x50; + +#[embassy::main] +async fn main(_spawner: Spawner, p: Peripherals) { + info!("Initializing TWI..."); + let config = twim::Config::default(); + let irq = interrupt::take!(SPIM0_SPIS0_TWIM0_TWIS0_SPI0_TWI0); + let mut twi = Twim::new(p.TWISPI0, irq, p.P0_03, p.P0_04, config); + + info!("Reading..."); + + let mut buf = [0u8; 16]; + twi.write_then_read(ADDRESS, &mut [0x00], &mut buf).unwrap(); + + info!("Read: {=[u8]:x}", buf); +} diff --git a/embassy-nrf-examples/src/bin/twim_lowpower.rs b/embassy-nrf-examples/src/bin/twim_lowpower.rs new file mode 100644 index 000000000..1cd66a18e --- /dev/null +++ b/embassy-nrf-examples/src/bin/twim_lowpower.rs @@ -0,0 +1,54 @@ +//! 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(min_type_alias_impl_trait)] +#![feature(impl_trait_in_bindings)] +#![feature(type_alias_impl_trait)] +#![allow(incomplete_features)] + +#[path = "../example_common.rs"] +mod example_common; + +use core::mem; + +use defmt::{panic, *}; +use embassy::executor::Spawner; +use embassy::time::{Duration, Timer}; +use embassy_nrf::twim::{self, Twim}; +use embassy_nrf::{interrupt, Peripherals}; + +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]; + twi.write_then_read(ADDRESS, &mut [0x00], &mut buf).unwrap(); + + 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; + } +}