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rp i2c: blocking example

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i2c example talking to mcp23017 i2c gpio expander.
This commit is contained in:
Jeremy Fitzhardinge 2022-09-29 02:01:58 -07:00
parent aabc02506b
commit 9f77dbf5ae
1 changed files with 70 additions and 0 deletions
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examples/rp/src/bin/i2c.rs Normal file
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#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::*;
use embassy_executor::Spawner;
use embassy_rp::i2c::{self, Config};
use embassy_time::{Duration, Timer};
use embedded_hal_1::i2c::blocking::I2c;
use {defmt_rtt as _, panic_probe as _};
#[allow(dead_code)]
mod mcp23017 {
pub const ADDR: u8 = 0x20; // default addr
pub const IODIRA: u8 = 0x00;
pub const IPOLA: u8 = 0x02;
pub const GPINTENA: u8 = 0x04;
pub const DEFVALA: u8 = 0x06;
pub const INTCONA: u8 = 0x08;
pub const IOCONA: u8 = 0x0A;
pub const GPPUA: u8 = 0x0C;
pub const INTFA: u8 = 0x0E;
pub const INTCAPA: u8 = 0x10;
pub const GPIOA: u8 = 0x12;
pub const OLATA: u8 = 0x14;
pub const IODIRB: u8 = 0x01;
pub const IPOLB: u8 = 0x03;
pub const GPINTENB: u8 = 0x05;
pub const DEFVALB: u8 = 0x07;
pub const INTCONB: u8 = 0x09;
pub const IOCONB: u8 = 0x0B;
pub const GPPUB: u8 = 0x0D;
pub const INTFB: u8 = 0x0F;
pub const INTCAPB: u8 = 0x11;
pub const GPIOB: u8 = 0x13;
pub const OLATB: u8 = 0x15;
}
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
let p = embassy_rp::init(Default::default());
let sda = p.PIN_14;
let scl = p.PIN_15;
info!("set up i2c ");
let mut i2c = i2c::I2c::new_blocking(p.I2C1, scl, sda, Config::default());
use mcp23017::*;
info!("init mcp23017 config for IxpandO");
// init - a outputs, b inputs
i2c.write(ADDR, &[IODIRA, 0x00]).unwrap();
i2c.write(ADDR, &[IODIRB, 0xff]).unwrap();
i2c.write(ADDR, &[GPPUB, 0xff]).unwrap(); // pullups
let mut val = 0xaa;
loop {
let mut portb = [0];
i2c.write(mcp23017::ADDR, &[GPIOA, val]).unwrap();
i2c.write_read(mcp23017::ADDR, &[GPIOB], &mut portb).unwrap();
info!("portb = {:02x}", portb[0]);
val = !val;
Timer::after(Duration::from_secs(1)).await;
}
}