base.c

#include "pico/multicore.h"
#include "pico/stdlib.h"

#include "base.h"

void set_led(int p)
{
	gpio_put(LED_PIN, !!p);
}

void blink(int on_ms, int off_ms)
{
	set_led(1);
	if (on_ms > 0) sleep_ms(on_ms);
	set_led(0);
	if (off_ms > 0) sleep_ms(off_ms);
}

// Panic and display error code using blink codes with the following repeating
// sequence:
//  - Fast strobe (signalling start of digit sequence)
//  - Pause
//  - For each non-zero hex digit, most significant first:
//     - Show hex digit as a series of blinks, one for 0x1, two for 0x2, etc
//     - Pause
// ( inspired by tinkering with an Audi 100 :-)
void PANIC(uint32_t error)
{
	// attempt to shut down things
	multicore_reset_core1();

	const int strobe_on_ms = 40;
	const int strobe_off_ms = 40;
	const int strobe_duration_ms = 500;
	const int digit_on_ms = 300;
	const int digit_off_ms = 200;
	const int pause_ms = 1500;
	const int n_hex_digits = sizeof(error)*2;
	while (1) {
		// strobe
		for (int t = 0; t <= strobe_duration_ms; t += (strobe_on_ms+strobe_off_ms)) {
			blink(strobe_on_ms, strobe_off_ms);
		}

		sleep_ms(pause_ms);

		// digits
		for (int i0 = 0; i0 < n_hex_digits; i0++) {
			int digit = (error >> (((n_hex_digits-1)-i0)<<2)) & 0xf;
			if (digit == 0) continue;
			for (int i1 = 0; i1 < digit; i1++) {
				blink(digit_on_ms, digit_off_ms);
			}
			sleep_ms(pause_ms);
		}
	}
}