Merge #993

993: rp i2c: blocking example r=Dirbaio a=jsgf

i2c example talking to mcp23017 i2c gpio expander.

Co-authored-by: Jeremy Fitzhardinge <jeremy@goop.org>

examples/rp/Cargo.toml

@@ -26,7 +26,7 @@ st7789 = "0.6.1"
 display-interface = "0.4.1"
 byte-slice-cast = { version = "1.2.0", default-features = false }
 
-embedded-hal-1 = { package = "embedded-hal", version = "1.0.0-alpha.8" }
+embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-alpha.9" }
 embedded-hal-async = { version = "0.1.0-alpha.1" }
 embedded-io = { version = "0.3.0", features = ["async", "defmt"] }
 static_cell = "1.0.0"

examples/rp/src/bin/i2c_blocking.rs

@@ -0,0 +1,70 @@
+#![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::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;
+    }
+}