Servo - March 2010

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by Dennis Clark

Well, the Christmas season has come and gone, and it appears that Santa was good to many of you robot builders out there since I’ve been getting some interesting questions. So, let’s get started!

Q. Regarding the October 2008 Zombie.zip article on the R/C receiver decoder. I found the referenced implementation of a “tank-like” RC decoder very elegant and would like to try it out myself.

1) Please elaborate on the minimum support PIC hardware that I will need to implement your R/C decoder solution (i.e., in detail what development platform was used for the PIC 18F252).

2) Please elaborate on where I can obtain the support software (i.e., CCS PCH compiler).

3) Can this solution be ported to the PIC 16 series or is the interrupt structure that you used the reason you chose to upgrade to the PIC 18 series of processors?

4) Are there any other articles or reference information that will assist me in testing out this solution? Many thanks.

— Stephen

A. That project was very minimal and I also felt elegant; thank you for noticing. I used the 18F252 just because it is a popular, all-around useful mid-range PIC. This project is pretty small code-wise, so one could go as small as the 18F2220 and have everything that I like in a chip — namely two PWM channels and a USART for debugging. This part is a little cheaper than the 18F252, as well.

You can get the CCS PCH compiler from Custom Computer Services, Inc.; their website is www.ccsinfo.com. They have a variety of reasonably priced compilers for the various PIC microcontrollers. PCH will integrate into the Microchip MPLAB IDE seamlessly.