ardupilot/ArduCopterMega/control_modes.pde

void read_control_switch()
{
	byte switchPosition = readSwitch();
	//motor_armed = (switchPosition < 5);
	
	if (oldSwitchPosition != switchPosition){
		if(motor_armed)
			Serial.println("motor_armed");
		else
			Serial.println("motor disarmed");
				
		set_mode(flight_modes[switchPosition]);
		
		oldSwitchPosition = switchPosition;

		// reset navigation integrators
		// -------------------------
		reset_I();
	}
}

byte readSwitch(void){
#if   FLIGHT_MODE_CHANNEL == CH_5
	int pulsewidth = rc_5.radio_in;			// default for Arducopter
#elif FLIGHT_MODE_CHANNEL == CH_6
	int pulsewidth = rc_6.radio_in;			//
#elif FLIGHT_MODE_CHANNEL == CH_7
	int pulsewidth = rc_7.radio_in;			//
#elif FLIGHT_MODE_CHANNEL == CH_8
	int pulsewidth = rc_8.radio_in;			// default for Ardupilot. Don't use for Arducopter! it has a hardware failsafe mux! 
#else
# error Must define FLIGHT_MODE_CHANNEL as CH_5 - CH_8
#endif

	if (pulsewidth > 1230 && pulsewidth <= 1360) 	return 1;
	if (pulsewidth > 1360 && pulsewidth <= 1490) 	return 2;
	if (pulsewidth > 1490 && pulsewidth <= 1620) 	return 3;
	if (pulsewidth > 1620 && pulsewidth <= 1749) 	return 4;	// Software Manual
	if (pulsewidth >= 1750) 						return 5;	// Hardware Manual
	return 0;
}

void reset_control_switch()
{
	oldSwitchPosition = -1;
	read_control_switch();
	//Serial.print("MSG: reset_control_switch");
	//Serial.println(oldSwitchPosition , DEC);
}

void update_servo_switches()
{

}

boolean trim_flag;
unsigned long trim_timer;

// read at 10 hz
// set this to your trainer switch
void read_trim_switch()
{
	// switch is engaged
	if (rc_7.radio_in > 1500){
		if(trim_flag == false){
			// called once
			trim_timer = millis();
		}
		trim_flag = true;
		//trim_accel();
		//Serial.println("trim_accels");
		
	}else{ // switch is disengaged
	
		if(trim_flag){
			// switch was just released
			if((millis() - trim_timer) > 2000){

				/*
				if(rc_3.control_in == 0){
					imu.init_accel();
					imu.print_accel_offsets();
				}*/
				Serial.printf("r: %d, p: %d\n", rc_1.control_in, rc_2.control_in);
				// set new accel offset values
				imu.ax(((long)rc_1.control_in * -15) / 100);
				imu.ay(((long)rc_2.control_in * -15) / 100);
				imu.print_accel_offsets();
			} else {
				// set the throttle nominal
				if(rc_3.control_in > 50){
					throttle_cruise = rc_3.control_in;
					Serial.print("tnom ");
					Serial.println(throttle_cruise, DEC);
					save_EEPROM_throttle_cruise();
				}
					
			}
			trim_flag = false;
		}
	}
}