display.c

/*
  Buffer visualisation thread.
 */
static WORKING_AREA(visual_wa, 128);
static msg_t visual(void *arg) {
  (void) arg;
  uint8_t col = 0;

  chRegSetThreadName("display_refresh");
  palWriteGroup(GPIOA, 0b11111111, 0, 0b00000000);

  while (!chThdShouldTerminate()) {
    palClearPad(GPIOA, col); // cols
    col = (col + 1) % DISPLAY_COLUMNS;
    chMtxLock(&mtx_page);
    PAGE* page = &pages[current_page];
    palWriteGroup(GPIOB, 0b11111111, 8, page->columns[col]);
    chMtxUnlock();
    palSetPad(GPIOA, col); // cols
    chThdSleepMilliseconds(3); // brightness
  }
  return 0;
}