Someone Posts a Code Example, Then What?

**dhouston** · - 10th June 2008, 13:17

I don't think I have schematics for each that use the PIC12F629 but my web page does have schematics of the basic circuits using similar chips (although they may use different pins). See...

http://davehouston.org/adc.htm
http://davehouston.org/generic-RF-RCVR.htm

For the transdmitter, I used a chip with ADC so I can modify the output to signal a low battery. If you are not interested in that, use the PIC12F629 and omit the connection to pin 6. Because I wanted to maximize battery life, the transmitter is powered by the data signal so there is no transmitter drain when idle.

For the receiver circuit you can use a PIC12F675 or the PIC12F683, as shown, if you want to measure received signal strength using an ADC pin (code will need modification). Otherwise, a PIC12F629 is fine.

NOTE: While the code uses a protocol developed about 40 years ago by NEC for IR remote control (TV, etc.), it's being used here for RF (as X-10 has used it for for nearly 40 years). If you want to use it with IR it's a bit different for both transmitting and receiving.

**jhorsburgh** · - 10th June 2008, 13:45

Hey Dave,
I plan on using IR in the future but for the moment i would like to get the RF working, the RS232 portion of the reciever is also something i would like to play with so the code you have posted is a perfect start.

Thanks again,
Jeremy

**dhouston** · - 10th June 2008, 14:53

The primary differences for IR are that you need to modulate the transmitter with the IR carrier frequency (usually 36-40kHz) and IR receivers are active low whereas RF receivers are active high. If you wander about my website you'll find a few schematics that may help. You can find more specific schematics on Bruce Reynols website...

http://www.rentron.com

Make sure that you are using the latest version of Code Studio. I believe the sample code was written for use with MPASM. If you want to use the meLabs PM assembler, you need to change the fuse config settings - there's a thread here that details the different syntaxes...