mirror of
https://github.com/italicsjenga/rp-hal-boards.git
synced 2024-12-24 13:11:30 +11:00
97 lines
2.9 KiB
Rust
97 lines
2.9 KiB
Rust
|
//! This example toggles the GPIO0 and GPIO1 pins, with each controlled from a
|
||
|
|
//! separate PIO state machine.
|
||
|
|
//!
|
||
|
|
//! Despite running in separate state machines, the clocks are sychronized at
|
||
|
|
//! the rise and fall times will be simultaneous.
|
||
|
|
#![no_std]
|
||
|
|
#![no_main]
|
||
|
|
|
||
|
|
use cortex_m_rt::entry;
|
||
|
|
use hal::gpio::{FunctionPio0, Pin};
|
||
|
|
use hal::pac;
|
||
|
|
use hal::pio::PIOExt;
|
||
|
|
use hal::Sio;
|
||
|
|
use panic_halt as _;
|
||
|
|
use rp2040_hal as hal;
|
||
|
|
|
||
|
|
#[link_section = ".boot2"]
|
||
|
|
#[used]
|
||
|
|
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
|
||
|
|
|
||
|
|
#[entry]
|
||
|
|
fn main() -> ! {
|
||
|
|
let mut pac = pac::Peripherals::take().unwrap();
|
||
|
|
|
||
|
|
let sio = Sio::new(pac.SIO);
|
||
|
|
let pins = hal::gpio::Pins::new(
|
||
|
|
pac.IO_BANK0,
|
||
|
|
pac.PADS_BANK0,
|
||
|
|
sio.gpio_bank0,
|
||
|
|
&mut pac.RESETS,
|
||
|
|
);
|
||
|
|
|
||
|
|
// configure pins for Pio0.
|
||
|
|
let _: Pin<_, FunctionPio0> = pins.gpio0.into_mode();
|
||
|
|
let _: Pin<_, FunctionPio0> = pins.gpio1.into_mode();
|
||
|
|
|
||
|
|
// PIN id for use inside of PIO
|
||
|
|
let pin0 = 0;
|
||
|
|
let pin1 = 1;
|
||
|
|
|
||
|
|
// Define some simple PIO program.
|
||
|
|
let program = pio_proc::pio_asm!(
|
||
|
|
"
|
||
|
|
.wrap_target
|
||
|
|
set pins, 1 [31]
|
||
|
|
set pins, 0 [31]
|
||
|
|
.wrap
|
||
|
|
"
|
||
|
|
);
|
||
|
|
|
||
|
|
// Initialize and start PIO
|
||
|
|
let (mut pio, sm0, sm1, _, _) = pac.PIO0.split(&mut pac.RESETS);
|
||
|
|
// I'm "measuring" the phase offset between the two pins by connecting
|
||
|
|
// then through a LED. If there is a clock offset, there will be a
|
||
|
|
// short time with a voltage between the pins, so the LED will flash up.
|
||
|
|
// With a slow clock this is not visible, so use a reasonably fast clock.
|
||
|
|
let div = 256f32;
|
||
|
|
|
||
|
|
let installed = pio.install(&program.program).unwrap();
|
||
|
|
let (mut sm0, _, _) = rp2040_hal::pio::PIOBuilder::from_program(installed)
|
||
|
|
.set_pins(pin0, 1)
|
||
|
|
.clock_divisor(div)
|
||
|
|
.build(sm0);
|
||
|
|
// The GPIO pin needs to be configured as an output.
|
||
|
|
sm0.set_pindirs([(pin0, hal::pio::PinDir::Output)]);
|
||
|
|
|
||
|
|
// NOTE: with the current rp-hal, I need to call pio.install() twice. This
|
||
|
|
// should be investigated further as it seems wrong.
|
||
|
|
let installed = pio.install(&program.program).unwrap();
|
||
|
|
let (mut sm1, _, _) = rp2040_hal::pio::PIOBuilder::from_program(installed)
|
||
|
|
.set_pins(pin1, 1)
|
||
|
|
.clock_divisor(div)
|
||
|
|
.build(sm1);
|
||
|
|
// The GPIO pin needs to be configured as an output.
|
||
|
|
sm1.set_pindirs([(pin1, hal::pio::PinDir::Output)]);
|
||
|
|
|
||
|
|
// Start both SMs at the same time
|
||
|
|
let group = sm0.with(sm1).sync().start();
|
||
|
|
cortex_m::asm::delay(10_000_000);
|
||
|
|
|
||
|
|
// Stop both SMs at the same time
|
||
|
|
let group = group.stop();
|
||
|
|
cortex_m::asm::delay(10_000_000);
|
||
|
|
|
||
|
|
// Start them again and extract the individual state machines
|
||
|
|
let (sm1, sm2) = group.start().free();
|
||
|
|
cortex_m::asm::delay(10_000_000);
|
||
|
|
|
||
|
|
// Stop the two state machines separately
|
||
|
|
let _sm1 = sm1.stop();
|
||
|
|
cortex_m::asm::delay(10_000_000);
|
||
|
|
let _sm2 = sm2.stop();
|
||
|
|
|
||
|
|
#[allow(clippy::empty_loop)]
|
||
|
|
loop {}
|
||
|
|
}
|