[Paparazzi-devel] servo controlling

[Matjaž Tome]

Dear sir!

I was amazed by the autopilot you made. I took a look at hardware schematics, and I realized, I don't understand how does servo control works. Why are servos connected to that logic integrated circuit, and not directly to microcontroller? If I understood rightly, microcontroller has built in PWM hardware, and I was wondering, why isn't it used? And my second question is, can this PWM module generates signal without of use of processor (can you set the period and duty cycle in some registers and then let the hardware do the job, or is the PWM module used only as a kind of timer, so when it generates interrupt, processor must change state of the pin)? Because in second case that would take some processor time, if you'd hat to control 4 servo motors.

 

I hope you will understand my question, and I apologize for my English.

All regards, Matjaž Tome