blink.pio

 
;
; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
;
; SPDX-License-Identifier: BSD-3-Clause
;

; SET pin 0 should be mapped to your LED GPIO

.program blink
    pull block
    out y, 32
.wrap_target
    mov x, y
    set pins, 1   ; Turn LED on
lp1:
    jmp x-- lp1   ; Delay for (x + 1) cycles, x is a 32 bit number
    mov x, y
    set pins, 0   ; Turn LED off
lp2:
    jmp x-- lp2   ; Delay for the same number of cycles again
.wrap             ; Blink forever!


% go {
// this is a raw helper function for use by the user which sets up the GPIO output, and configures the SM to output on a particular pin
func blinkProgramInit(sm *machine.PIOStateMachine, offset uint8, pin machine.Pin) {
	pin.Configure(machine.PinConfig{Mode: machine.PinPIO0})
	sm.SetConsecutivePinDirs(pin, 1, true)
	cfg := blinkProgramDefaultConfig(offset)
	cfg.SetSetPins(pin, 1)
	sm.Init(offset, &cfg)
}
%}