Copy pico_i2c_pio example from rp-hal

.cargo/config

@@ -0,0 +1,41 @@
+#
+# Cargo Configuration for the https://github.com/rp-rs/rp-hal.git repository.
+#
+# Copyright (c) The RP-RS Developers, 2021
+#
+# The copy in this repository is only used for compiling examples.
+#
+# This file is MIT or Apache-2.0 as per the repository README.md file
+#
+
+[build]
+# Set the default target to match the Cortex-M0+ in the RP2040
+target = "thumbv6m-none-eabi"
+
+# Target specific options
+[target.thumbv6m-none-eabi]
+# Pass some extra options to rustc, some of which get passed on to the linker.
+#
+# * linker argument --nmagic turns off page alignment of sections (which saves
+#   flash space)
+# * linker argument -Tlink.x tells the linker to use link.x as the linker
+#   script. This is usually provided by the cortex-m-rt crate, and by default
+#   the version in that crate will include a file called `memory.x` which
+#   describes the particular memory layout for your specific chip. 
+# * inline-threshold=5 makes the compiler more aggressive and inlining functions
+# * no-vectorize-loops turns off the loop vectorizer (seeing as the M0+ doesn't
+#   have SIMD)
+rustflags = [
+    "-C", "link-arg=--nmagic",
+    "-C", "link-arg=-Tlink.x",
+    "-C", "inline-threshold=5",
+    "-C", "no-vectorize-loops",
+]
+
+# This runner will make a UF2 file and then copy it to a mounted RP2040 in USB
+# Bootloader mode:
+runner = "elf2uf2-rs -d"
+
+# This runner will find a supported SWD debug probe and flash your RP2040 over
+# SWD:
+# runner = "probe-run --chip RP2040"

Cargo.toml

@@ -17,3 +17,8 @@ embedded-time = "0.12.0"
 nb = "1.0.0"
 pio = "0.2.0"
 rp2040-hal = "0.4.0"
+
+[dev-dependencies]
+panic-halt= "0.2.0"
+rp-pico = "0.3.0"
+cortex-m-rt = { version = "0.7" }

examples/pico_i2c_pio.rs

@@ -0,0 +1,156 @@
+//! # Pico I2C PIO Example
+//!
+//! Reads the temperature from an LM75B
+//!
+//! This read over I2C the temerature from an LM75B temperature sensor wired on pins 20 and 21
+//! using the PIO peripheral as an I2C bus controller.
+//! The pins used for the I2C can be remapped to any other pin available to the PIO0 peripheral.
+//!
+//! See the `Cargo.toml` file for Copyright and license details.
+
+#![no_std]
+#![no_main]
+
+// The trait used by formatting macros like write! and writeln!
+use core::fmt::Write as FmtWrite;
+
+// The macro for our start-up function
+use cortex_m_rt::entry;
+
+// I2C HAL traits & Types.
+use embedded_hal::blocking::i2c::{Operation, Read, Transactional, Write};
+
+// Time handling traits
+use embedded_time::rate::*;
+
+// Ensure we halt the program on panic (if we don't mention this crate it won't
+// be linked)
+use panic_halt as _;
+
+// Pull in any important traits
+use rp_pico::hal::prelude::*;
+
+// A shorter alias for the Peripheral Access Crate, which provides low-level
+// register access
+use rp_pico::hal::pac;
+
+// A shorter alias for the Hardware Abstraction Layer, which provides
+// higher-level drivers.
+use rp_pico::hal;
+
+/// Prints the temperature received from the sensor
+fn print_temperature(serial: &mut impl FmtWrite, temp: [u8; 2]) {
+    let temp_i16 = i16::from_be_bytes(temp) >> 5;
+    let temp_f32 = f32::from(temp_i16) * 0.125;
+
+    // Write formatted output but ignore any error.
+    let _ = writeln!(serial, "Temperature: {:0.2}°C", temp_f32);
+}
+
+/// Entry point to our bare-metal application.
+///
+/// The `#[entry]` macro ensures the Cortex-M start-up code calls this function
+/// as soon as all global variables are initialised.
+///
+/// The function configures the RP2040 peripherals, reads the temperature from
+/// the attached LM75B using PIO0.
+#[entry]
+fn main() -> ! {
+    // Grab our singleton objects
+    let mut pac = pac::Peripherals::take().unwrap();
+
+    // Set up the watchdog driver - needed by the clock setup code
+    let mut watchdog = hal::Watchdog::new(pac.WATCHDOG);
+
+    // Configure the clocks
+    //
+    // The default is to generate a 125 MHz system clock
+    let clocks = hal::clocks::init_clocks_and_plls(
+        rp_pico::XOSC_CRYSTAL_FREQ,
+        pac.XOSC,
+        pac.CLOCKS,
+        pac.PLL_SYS,
+        pac.PLL_USB,
+        &mut pac.RESETS,
+        &mut watchdog,
+    )
+    .ok()
+    .unwrap();
+
+    // The single-cycle I/O block controls our GPIO pins
+    let sio = hal::Sio::new(pac.SIO);
+
+    // Set the pins up according to their function on this particular board
+    let pins = rp_pico::Pins::new(
+        pac.IO_BANK0,
+        pac.PADS_BANK0,
+        sio.gpio_bank0,
+        &mut pac.RESETS,
+    );
+
+    let uart_pins = (
+        // UART TX (characters sent from RP2040) on pin 1 (GPIO0)
+        pins.gpio0.into_mode::<hal::gpio::FunctionUart>(),
+        // UART RX (characters received by RP2040) on pin 2 (GPIO1)
+        pins.gpio1.into_mode::<hal::gpio::FunctionUart>(),
+    );
+
+    let mut uart = hal::uart::UartPeripheral::new(pac.UART0, uart_pins, &mut pac.RESETS)
+        .enable(
+            hal::uart::common_configs::_115200_8_N_1,
+            clocks.peripheral_clock.into(),
+        )
+        .unwrap();
+
+    let (mut pio, sm0, _, _, _) = pac.PIO0.split(&mut pac.RESETS);
+
+    let mut i2c_pio = i2c_pio::I2C::new(
+        &mut pio,
+        pins.gpio20,
+        pins.gpio21,
+        sm0,
+        100_000.Hz(),
+        clocks.system_clock.freq(),
+    );
+
+    let mut temp = [0; 2];
+    i2c_pio
+        .read(0x48u8, &mut temp)
+        .expect("Failed to read from the peripheral");
+    print_temperature(&mut uart, temp);
+
+    i2c_pio
+        .write(0x48u8, &[0])
+        .expect("Failed to write to the peripheral");
+
+    let mut temp = [0; 2];
+    i2c_pio
+        .read(0x48u8, &mut temp)
+        .expect("Failed to read from the peripheral");
+    print_temperature(&mut uart, temp);
+
+    let mut config = [0];
+    let mut thyst = [0; 2];
+    let mut tos = [0; 2];
+    let mut temp = [0; 2];
+    let mut operations = [
+        Operation::Write(&[1]),
+        Operation::Read(&mut config),
+        Operation::Write(&[2]),
+        Operation::Read(&mut thyst),
+        Operation::Write(&[3]),
+        Operation::Read(&mut tos),
+        Operation::Write(&[0]),
+        Operation::Read(&mut temp),
+    ];
+    i2c_pio
+        .exec(0x48u8, &mut operations)
+        .expect("Failed to run all operations");
+    print_temperature(&mut uart, temp);
+
+    loop {
+        cortex_m::asm::nop();
+    }
+}
+
+// End of file

memory.x

@@ -0,0 +1,17 @@
+/* This file is only used for compiling examples */
+
+MEMORY {
+    BOOT2 : ORIGIN = 0x10000000, LENGTH = 0x100
+    FLASH : ORIGIN = 0x10000100, LENGTH = 2048K - 0x100
+    RAM   : ORIGIN = 0x20000000, LENGTH = 256K
+}
+
+EXTERN(BOOT2_FIRMWARE)
+
+SECTIONS {
+    /* ### Boot loader */
+    .boot2 ORIGIN(BOOT2) :
+    {
+        KEEP(*(.boot2));
+    } > BOOT2
+} INSERT BEFORE .text;