void entry(void)
{
int8_t tag_angle;
/* set advertisment packet */
radio_advertise(&g_beacon_pkt, sizeof(g_beacon_pkt));
/* run advertisement in background every 995ms */
radio_interval_ms(995);
/* infinite foreground loop */
while(TRUE)
{
/* get tag angle from 3D accelerometer */
acc_magnitude(&tag_angle);
/* only tx while beacon is worn (facing forward +/-45 degree) */
radio_enable(abs(tag_angle)<45);
/* blink once every three seconds */
timer_wait_ms(3000);
pin_set(CONFIG_LED_PIN);
timer_wait_ms(1);
pin_clear(CONFIG_LED_PIN);
}
}
int main()
{
// Disable, configure, and start the watchdog timer
wdt_disable();
wdt_reset();
wdt_enable(WDTO_8S);
// Start and configure all hardware peripherals
sei();
led_init();
radio_init();
gps_init();
radio_enable();
// Set the radio shift and baud rate
_radio_dac_write(RADIO_COARSE, RADIO_CENTER_FREQ);
_radio_dac_write(RADIO_FINE, 0);
radio_set_shift(RADIO_SHIFT_425);
radio_set_baud(RADIO_BAUD_50);
// Radio chatter
for(uint8_t i = 0; i < 5; i++)
{
radio_chatter();
wdt_reset();
}
int32_t lat = 0, lon = 0, alt = 0;
uint8_t hour = 0, minute = 0, second = 0, lock = 0, sats = 0;
while(true)
{
led_set(LED_GREEN, 1);
// Get the current system tick and increment
uint32_t tick = eeprom_read_dword(&ticks) + 1;
// Check that we're in airborne <1g mode
if( gps_check_nav() != 0x06 ) led_set(LED_RED, 1);
// Get information from the GPS
gps_check_lock(&lock, &sats);
if( lock == 0x02 || lock == 0x03 || lock == 0x04 )
{
gps_get_position(&lat, &lon, &alt);
gps_get_time(&hour, &minute, &second);
}
led_set(LED_GREEN, 0);
// Format the telemetry string & transmit
double lat_fmt = (double)lat / 10000000.0;
double lon_fmt = (double)lon / 10000000.0;
alt /= 1000;
sprintf(s, "$$" CALLSIGN ",%lu,%02u:%02u:%02u,%02.7f,%03.7f,%ld,%u,%x",
tick, hour, minute, second, lat_fmt, lon_fmt, alt,
sats, lock);
radio_chatter();
radio_transmit_sentence(s);
radio_chatter();
led_set(LED_RED, 0);
eeprom_update_dword(&ticks, tick);
wdt_reset();
_delay_ms(500);
}
return 0;
}
