General • PIO for sensing hall signal

Code:

.program hall.wrap_targetloop:    in pins 3    mov y ISR    jmp x != y send    jmp loop    send:    push    mov x y.wrap% c-sdk {static inline void hall_program_init(PIO pio, uint sm, uint offset, uint pin) {   for (uint i = 0; i < 3; i++) {     pio_gpio_init(pio, pin + i);   }   pio_sm_set_consecutive_pindirs(pio, sm, pin, 3, false);   pio_sm_config c = hall_program_get_default_config(offset);   sm_config_set_in_shift(&c, false, false, 3);   sm_config_set_in_pins(&c, pin);   pio_sm_init(pio, sm, offset, &c);}%}

Code:

#include <stdio.h>#include "pico/stdlib.h"#include "hardware/pio.h"#include "hall.pio.h"int main() {    stdio_init_all();    PIO pio = pio0;    int smHall = pio_claim_unused_sm(pio, true);    uint offsetHall = pio_add_program(pio, &hall_program);    const uint8_t hall_pin = 26;    const uint8_t hall_enable = 9;    printf("Loaded hall program at %d\n", offsetHall);    gpio_init(hall_enable);    gpio_set_dir(hall_enable, GPIO_OUT);    gpio_put(hall_enable, 0);    for (uint8_t i = 0; i < 3; i++) {      gpio_init(hall_pin + i);      gpio_set_dir(hall_pin + i, GPIO_IN);    }    hall_program_init(pio, smHall, offsetHall, hall_pin);    pio_sm_set_enabled(pio, smHall, true);    while (true) {        if (!pio_sm_is_rx_fifo_empty(pio, smHall)) {            uint32_t hallPattern = pio_sm_get(pio, smHall);            printf("Hall pattern: %b\n", hallPattern);        }    }}

Code:

Hall pattern: 101101Hall pattern: 101Hall pattern: 101101Hall pattern: 101Hall pattern: 101101Hall pattern: 101