Im currently in the making of a radio-controller for my robot, to tell it when its allowed to drive and when its not.
The deal is that whenever the radiocontroller is on, the radioreciever sends out a PWM signal with a 1,5ms peak of a total 20ms. When the radiocontroller is off, its no peak in this signal (just low).
So right now for the override function basically reads if there is any high value on the port the radioreciever is connected to. If it reads any signal from the radioreciever, the robot should continue with its regular code. If not, it should stand still with the servo centered and motorcontroller "centered" (they are quiet when its a PWM signal with 1,5 ms peaks).
The problem here is that its very much noise, so the car will some times go even if the radiocontroller is off. This is because it just needs a peak in the signal, but it doesnt care how long the peak is. In my example, I need it to look for 1.5 ms long peaks to reduce the possibility of noise activating the rest of the code.
So anyone know where I could start for reading PWM signals into axon?
Thanks for any help.
edit; here's the code for the function as it is now
void checkSignal(void)
{
#define PINNR 3 //Connected to PIN A3
#define DDR DDRA
#define PORT PORTA
#define PIN PINA
PORT_ON(DDR, PINGPIN); //Turn port A3 on
FLIP_PORT(DDR, PINGPIN); //Turning output port into input port
if (bit_is_set(PIN, PINNR)==0) //if there is no signal coming from control unit
{
pwmSetH4(1500); //turn motor to "quiet mode"
pwmSetH3(1550); //center servo
}
loop_until_bit_is_set(PIN, PINNR); //Loop this until signal is coming from control unit
PORT_OFF(PORT, PINNR); //Turn port A3 off, not sure if necassary
}
