// *************************************************************************************************
// @fn start_altitude_measurement
// @brief Start altitude measurement
// @param none
// @return none
// *************************************************************************************************
void start_altitude_measurement(void)
{
// Show warning if pressure sensor was not initialised properly
if (!ps_ok)
{
display_chars(LCD_SEG_L1_2_0, (u8*)"ERR", SEG_ON);
return;
}
// Start altitude measurement if timeout has elapsed
if (sAlt.timeout == 0)
{
// Enable DRDY IRQ on rising edge
PS_INT_IFG &= ~PS_INT_PIN;
PS_INT_IE |= PS_INT_PIN;
// Start pressure sensor
ps_start();
// Set timeout counter only if sensor status was OK
sAlt.timeout = ALTITUDE_MEASUREMENT_TIMEOUT;
// Get updated altitude
while((PS_INT_IN & PS_INT_PIN) == 0);
do_altitude_measurement(FILTER_OFF);
}
}
// *************************************************************************************************
// @fn start_altitude_measurement
// @brief Start altitude measurement
// @param none
// @return none
// *************************************************************************************************
void start_altitude_measurement(void)
{
u8 timeout = 15;
// Already on?
if (sAlt.on)
return;
// Show warning if pressure sensor was not initialised properly
if (!ps_ok)
{
display_chars(LCD_SEG_L1_2_0, (u8 *) "ERR", SEG_ON);
return;
}
// Enable DRDY IRQ on rising edge
PS_INT_IFG &= ~PS_INT_PIN;
PS_INT_IE |= PS_INT_PIN;
// Start pressure sensor
ps_start();
// Set altitude measurement flag
sAlt.on = 1;
// Get updated altitude
while (((PS_INT_IN & PS_INT_PIN) == 0) && (timeout > 0))
{
Timer0_A4_Delay(CONV_MS_TO_TICKS(100));
timeout--;
}
// Failed to start?
if (timeout == 0)
{
sAlt.on = 0;
}
do_altitude_measurement(FILTER_OFF);
}
