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https://github.com/italicsjenga/rp-hal-boards.git
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0e2b4cf7be
* pio: Changes `PIOBuilder::clock_divisor` from f32 to fixed point) * pio: mark clock_divisor as deprecated
76 lines
2.4 KiB
Rust
76 lines
2.4 KiB
Rust
//! This example toggles the GPIO25 pin, using a PIO program.
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//!
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//! If a LED is connected to that pin, like on a Pico board, the LED should blink.
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#![no_std]
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#![no_main]
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use hal::gpio::{FunctionPio0, Pin};
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use hal::pac;
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use hal::pio::PIOExt;
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use hal::Sio;
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use panic_halt as _;
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use rp2040_hal as hal;
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#[link_section = ".boot2"]
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#[used]
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pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_GENERIC_03H;
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/// Entry point to our bare-metal application.
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///
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/// The `#[rp2040_hal::entry]` macro ensures the Cortex-M start-up code calls this function
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/// as soon as all global variables and the spinlock are initialised.
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///
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/// The function configures the RP2040 peripherals, then blinks an LED using the PIO peripheral.
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#[rp2040_hal::entry]
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fn main() -> ! {
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let mut pac = pac::Peripherals::take().unwrap();
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let sio = Sio::new(pac.SIO);
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let pins = hal::gpio::Pins::new(
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pac.IO_BANK0,
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pac.PADS_BANK0,
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sio.gpio_bank0,
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&mut pac.RESETS,
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);
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// configure LED pin for Pio0.
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let _led: Pin<_, FunctionPio0> = pins.gpio25.into_mode();
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// PIN id for use inside of PIO
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let led_pin_id = 25;
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// Define some simple PIO program.
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const MAX_DELAY: u8 = 31;
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let mut a = pio::Assembler::<32>::new();
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let mut wrap_target = a.label();
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let mut wrap_source = a.label();
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// Set pin as Out
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a.set(pio::SetDestination::PINDIRS, 1);
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// Define begin of program loop
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a.bind(&mut wrap_target);
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// Set pin low
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a.set_with_delay(pio::SetDestination::PINS, 0, MAX_DELAY);
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// Set pin high
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a.set_with_delay(pio::SetDestination::PINS, 1, MAX_DELAY);
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// Define end of program loop
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a.bind(&mut wrap_source);
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// The labels wrap_target and wrap_source, as set above,
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// define a loop which is executed repeatedly by the PIO
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// state machine.
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let program = a.assemble_with_wrap(wrap_source, wrap_target);
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// Initialize and start PIO
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let (mut pio, sm0, _, _, _) = pac.PIO0.split(&mut pac.RESETS);
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let installed = pio.install(&program).unwrap();
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let (int, frac) = (0, 0); // as slow as possible (0 is interpreted as 65536)
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let (sm, _, _) = rp2040_hal::pio::PIOBuilder::from_program(installed)
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.set_pins(led_pin_id, 1)
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.clock_divisor_fixed_point(int, frac)
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.build(sm0);
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sm.start();
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// PIO runs in background, independently from CPU
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loop {
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cortex_m::asm::wfi();
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}
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}
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