RC Servo decoding/encoding using 12F683

[ScaleRobotics]

What is the purpose/function of this?

Good question. Think of it as a platform. Most applications I can dream up for it are RC based.

Say you have a simple minded receiver and transmitter, but you want to do your own aileron/rudder/elevator mixing - go ahead, just write some code. Even do some IR leveling of your plane ... go ahead...

Say your receiver gives some bogus pulses out when it looses your transmitter signal for a second or two - you can filter these out, go to last good signal, or a default setting for that servo.

Say you want to build an autonomous vehicle, but still have the option of controlling it with your transmitter. Set autopilot on/off using channel 5.

Say you want to build an altitude hold circuit. This is a perfect platform. (Ok, maybe not quite perfect yet, but should be close once I sync to ch1)

Since all the pulses are done using interrupts (and no blocking loops like pause, pulsin, pulsout), there is a lot of time in between to do what ever you want it to do.

What's the use of the PIC, why not simply connect 4 servos direct to the RC receiver and get the same result ?

Because then you could not do any of the above.