SERIN Timeout

[skimask]

Yeah, have written the code for the sender so can change that to whatever, I've got "READY" as my qualifier. I'm going to try your idea about using a very short timeout to see how it works 1-2ms I'm thinking at the moment - will be interesting if nothing else to see what effect it has on the time keeping. Thanks for all yr input so far

I just saw that your baud rate is 2400. That's .416 us per bit, a start bit is generally 1.5 bit lengths, which gives you .625us for a start bit. Timeout is limited to 1 ms minimum, it might work, it might not. You might end up waiting for READY, but only able to receive "EADY". I would think if you sent a string of qualifiers (bunch of $AA55's or the like), say 10 of them, wait until you have a solid 5 received, then you should be able to dispense with any timeouts because you signal is strong enough to get the qual's.

[George]

I've got a string of 5 $AA preceeeding the READY, and haven't seemed to have much of a problem getting the data to the receiver - i send the data 5 times on a transmission to make fairly sure it gets through. I've got the timeout at 1ms toggling an LED to indicate to me when it's exiting out of the serin command - it's way random tho can tripout every half second or every 10 minutes. The issue I have is not so much transmitting the data - it's when no data is being transmitted

[George]

Oh the other thing I forgot to mention is that the RF modules r AM so there is alot of static when there is no carrier

[skimask]

Oh the other thing I forgot to mention is that the RF modules r AM so there is alot of static when there is no carrier

ooofff...AM...that hurts
Still, send the data multiple times, add a checksum to the data, receive the data successfully X number of times, blah blah blah... Should be too much of a problem even with all that random AM static noise.
But you're still on the problem of sitting in a SERIN loop waiting for solid data while you still need to do other stuff, correct? How about a 2nd PIC (say a 16F688) that just sits there and waits for data, and when it gets good data, it fires it out a different serial port to the 'real' PIC, which doesn't have to worry about garbage data... Heck, might even be a good spot for a 10F202 to handle that job!!!

[George]

Yah - I wanted to avoid something like that due to complexity - plus haven't had any luck with PBP and 10F202 (PBP uses up too many variables - tho for a simple job like that I'm sure it would work) electronically it's prolly simpler for me to build a squelch. I might do a new post with a title more reflecting ASM interupts - thanks for all yr input

[mister_e]

unless your module have a RSS output, send it to the trash can.

[Archangel]

Oh the other thing I forgot to mention is that the RF modules r AM so there is alot of static when there is no carrier

Can you not install a squelch circuit on the receiver?

[mister_e]

Or feed it to a PIC comparator input

Sorry if this sounds like a PMS reply but we still don't know which RF module you're using.