rp-hal-boards/rp2040-hal/examples/uart.rs

68 lines
1.6 KiB
Rust
Raw Normal View History

//! Print an incrementing number to UART0 in a loop
#![no_std]
#![no_main]
use core::fmt::Write;
use cortex_m_rt::entry;
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;
use panic_halt as _;
use rp2040_hal as hal;
#[link_section = ".boot2"]
#[used]
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
#[entry]
fn main() -> ! {
let mut pac = pac::Peripherals::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
let external_xtal_freq_hz = 12_000_000u32;
let clocks = init_clocks_and_plls(
external_xtal_freq_hz,
pac.XOSC,
pac.CLOCKS,
pac.PLL_SYS,
pac.PLL_USB,
&mut pac.RESETS,
&mut watchdog,
)
.ok()
.unwrap();
let pins = Pins::new(
pac.IO_BANK0,
pac.PADS_BANK0,
sio.gpio_bank0,
&mut pac.RESETS,
);
let mut uart = UartPeripheral::<_, _>::enable(
pac.UART0,
&mut pac.RESETS,
hal::uart::common_configs::_9600_8_N_1,
clocks.peripheral_clock.into(),
)
.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>();
uart.write_full_blocking(b"UART example\r\n");
let mut value = 0u32;
loop {
writeln!(uart, "value: {:02}\r", value).unwrap();
cortex_m::asm::delay(10_000_000);
value += 1
}
}