36 lines
1.2 KiB
Plaintext
36 lines
1.2 KiB
Plaintext
.program CLK
|
|
.side_set 1 opt
|
|
|
|
irq clear 0 side 1 ; Set IRQ for other signals to reference off of
|
|
mov y, isr ; ISR contains PWM period. Y used as counter.
|
|
irq 0
|
|
countloop:
|
|
jmp x!=y noset ; Set pin high if X == Y, keep the two paths length matched
|
|
jmp skip side 0
|
|
noset:
|
|
nop ; Single dummy cycle to keep the two paths the same length
|
|
skip:
|
|
jmp y-- countloop ; Loop until Y hits 0, then pull a restart the counter
|
|
|
|
|
|
|
|
% c-sdk {
|
|
static inline void CLK_program_init(PIO pio, uint sm, uint offset, uint pin) {
|
|
pio_sm_config c = CLK_program_get_default_config(offset);
|
|
|
|
// Map the state machine's OUT pin group to one pin, namely the `pin`
|
|
// parameter to this function.
|
|
sm_config_set_out_pins(&c, pin, 1);
|
|
// Set this pin's GPIO function (connect PIO to the pad)
|
|
pio_gpio_init(pio, pin);
|
|
// Set the pin direction to output at the PIO
|
|
pio_sm_set_consecutive_pindirs(pio, sm, pin, 1, true);
|
|
|
|
sm_config_set_sideset_pins(&c, pin);
|
|
|
|
// Load our configuration, and jump to the start of the program
|
|
pio_sm_init(pio, sm, offset, &c);
|
|
// Set the state machine running
|
|
//pio_sm_set_enabled(pio, sm, true);
|
|
}
|
|
%} |