git.scottworley.com Git - tattlekey/blob - client/button.c

   1 #include "button.h"
   2 #include "config.h"
   3
   4 #include "hardware/gpio.h"
   5
   6 #include "pico/stdlib.h"
   7
   8 static callback_t button_callback = NULL;
   9
  10 static void respond_to_gpio_interrupt(uint gpio, uint32_t event_mask) {
  11   if (gpio == button_pin && event_mask & GPIO_IRQ_EDGE_FALL &&
  12       button_callback) {
  13     button_callback();
  14   }
  15 }
  16
  17 void begin_listening_for_button_press(callback_t callback) {
  18   button_callback = callback;
  19
  20   gpio_set_pulls(button_pin, 1, 0);
  21
  22   /* Allow some time for the pull-up to take effect.
  23    * I'm not sure if this is necessary.
  24    * https://datasheets.raspberrypi.com/pico/raspberry-pi-pico-c-sdk.pdf says
  25    * the internal GPIO pull-up resistors are 50k. */
  26   sleep_ms(100);
  27
  28   gpio_set_irq_enabled_with_callback(button_pin, GPIO_IRQ_EDGE_FALL, 1,
  29                                      respond_to_gpio_interrupt);
  30 }