Quote Originally Posted by microuser
Ok, now I have a little problem!
I have tested the system with three tx and ten rx, and it works! but now I have five tx(16f648a) and ten rx(16f648a) on the same serial line. Each transmitter have a 1k resistor on the tx pin. I use serout2 and serin2 command. Now I think I have a signal problem because any rx doesn't receive the signal! I check it with a scope and I can see that for every tx that I add to the system the signal go down of little.
How can I do for make all work? Help me please!

thanks in advance!
If your transmitters are at different logic levels then the combination of resistors will attenuate the level on your data line and you will get indeterminate logic levels.

If the pins normally idle high then tie your data line high with a pullup resistor and use a diode from each transmitter pin to pull the line down when active.

If the line is normally idle low then use a pull down resistor, flip the diodes the other way and then the active transmitter can drive the data line.

The diodes will "OR" the signals together thereby avoiding shorting out any PICs and provided only one transmitter is sending at any one time it should work fine.

DISCLAIMER: I havent actually tried this but it is how I am planning to do a similar application!!!

Someone please stop me in advance if there is a better way of doing this

Regards