Update ADC example.

This commit is contained in:
Jonathan Pallant (42 Technology) 2021-09-27 14:42:19 +01:00
parent 0fa6bf9e0e
commit ed27dc9949

View file

@ -1,40 +1,66 @@
//! Read ADC samples from the temperature sensor and pin and
//! output them to the UART on pins 1 and 2 at 9600 baud
//! # ADC Example
//!
//! This application demonstrates how to read ADC samples from the temperature
//! sensor and pin and output them to the UART on pins 1 and 2 at 9600 baud.
//!
//! It may need to be adapted to your particular board layout and/or pin assignment.
//!
//! See the `Cargo.toml` file for Copyright and licence details.
#![no_std]
#![no_main]
use core::fmt::Write;
use cortex_m::prelude::_embedded_hal_adc_OneShot;
// The macro for our start-up function
use cortex_m_rt::entry;
use hal::adc::Adc;
use hal::clocks::init_clocks_and_plls;
use hal::gpio::{self, Pins};
use hal::pac;
use hal::sio::Sio;
use hal::uart::UartPeripheral;
use hal::watchdog::Watchdog;
// Ensure we halt the program on panic (if we don't mention this crate it won't
// be linked)
use panic_halt as _;
// Alias for our HAL crate
use rp2040_hal as hal;
// An ADC trait we need
use embedded_hal::adc::OneShot;
// A debug/string formatting trait we need
use core::fmt::Write;
// A shorter alias for the Peripheral Access Crate, which provides low-level
// register access
use hal::pac;
// The linker will place this boot block at the start of our program image. We
// need this to help the ROM bootloader get our code up and running.
#[link_section = ".boot2"]
#[used]
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
// External high-speed crystal on the pico board is 12Mhz
// Adjust if your board has a different frequency
/// External high-speed crystal on the Raspberry Pi Pico board is 12 MHz. Adjust
/// if your board has a different frequency
const XTAL_FREQ_HZ: u32 = 12_000_000u32;
/// Run RP2040 at 125 MHz
const SYS_FREQ_HZ: u32 = hal::pll::common_configs::PLL_SYS_125MHZ.vco_freq.0;
/// 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, then prints the temperature
/// in an infinite loop.
#[entry]
fn main() -> ! {
// Grab our singleton objects
let mut pac = pac::Peripherals::take().unwrap();
let core = pac::CorePeripherals::take().unwrap();
let mut watchdog = Watchdog::new(pac.WATCHDOG);
let sio = Sio::new(pac.SIO);
// External high-speed crystal on the pico board is 12Mhz
// Set up the watchdog driver - needed by the clock setup code
let mut watchdog = hal::watchdog::Watchdog::new(pac.WATCHDOG);
let clocks = init_clocks_and_plls(
// Configure the clocks
let clocks = hal::clocks::init_clocks_and_plls(
XTAL_FREQ_HZ,
pac.XOSC,
pac.CLOCKS,
@ -46,16 +72,23 @@ fn main() -> ! {
.ok()
.unwrap();
// The delay object lets us wait for specified amounts of time (in
// milliseconds)
let mut delay = cortex_m::delay::Delay::new(core.SYST, SYS_FREQ_HZ);
let pins = Pins::new(
// The single-cycle I/O block controls our GPIO pins
let sio = hal::sio::Sio::new(pac.SIO);
// Set the pins to their default state
let pins = hal::gpio::Pins::new(
pac.IO_BANK0,
pac.PADS_BANK0,
sio.gpio_bank0,
&mut pac.RESETS,
);
let mut uart = UartPeripheral::<_, _>::enable(
// Create a UART driver
let mut uart = hal::uart::UartPeripheral::<_, _>::enable(
pac.UART0,
&mut pac.RESETS,
hal::uart::common_configs::_9600_8_N_1,
@ -64,14 +97,19 @@ fn main() -> ! {
.unwrap();
// UART TX (characters sent from pico) on pin 1 (GPIO0) and RX (on pin 2 (GPIO1)
let _tx_pin = pins.gpio0.into_mode::<gpio::FunctionUart>();
let _rx_pin = pins.gpio1.into_mode::<gpio::FunctionUart>();
let _tx_pin = pins.gpio0.into_mode::<hal::gpio::FunctionUart>();
let _rx_pin = pins.gpio1.into_mode::<hal::gpio::FunctionUart>();
// Write to the UART
uart.write_full_blocking(b"ADC example\r\n");
// Enable adc
let mut adc = Adc::new(pac.ADC, &mut pac.RESETS);
// Enable ADC
let mut adc = hal::adc::Adc::new(pac.ADC, &mut pac.RESETS);
// Enable the temperature sense channel
let mut temperature_sensor = adc.enable_temp_sensor();
// Configure one of the pins as an ADC input as well.
// Configure GPIO26 as an ADC input
let mut adc_pin_0 = pins.gpio26.into_floating_input();
loop {
// Read the raw ADC counts from the temperature sensor channel.
@ -86,3 +124,5 @@ fn main() -> ! {
delay.delay_ms(1000);
}
}
// End of file