Quote Originally Posted by George View Post
Any idea's on squelch circuit? I was thinking about using an LM358 opamp putting the RSSI and a threshold into one amp then the output of that (maybe thru a divider) to the input of the other amp alongside data to get a squelched output?

I think MELabs should modify their code for the serin timeout and supply a timeout feature that will timeout if the qualifier isn't met within the timeout period I realise this would be more difficult - but I've spent hours fluffing around on what should be such a simple project - monitoring an RF receiver and counting down the time - i can't exit from the serin cos the static noise on the line resets the timer in the serin command, i can't use Darryl's wonderful interupt file cos it chews up all my variables, i can use an asm interupt cos I'm not really advanced enough to figure it out. Hopefully the squelch will work albeit with what probably is a significant reduction in range.

I do like Mister_e's concept of looking at a USART - I might have a quick look in2 that before I build my squelch
Definetely use the hardware USART...many advantages...not to mention you learn a bit about. A bit of a steep learning curve...not too bad though...
The op-amp...somehow I get the feeling that the op-amp idea will pick up just as much noise as the raw data stream itself and you'll be getting loads of false interrupts.