Quote Originally Posted by Jerson View Post
There are a couple of things I can think of.

Try increasing the preamble bytes $55. So, you send $55,$55,$55,$55,$55,$66,[data]
Try flagging the capture of qualifier in receive module to the LCD. So, you know if it is being captured correctly.
2 more preamble bytes!!!! Now I send $55,$55,$55,$55,$66,data and the amount of correct data received(and displayed on lcd) is more than 90%

I've also made a few changes: there is now a 5msec pause after the txer is switched on. 2400bps now works fine.

On the monitoring side I chenaged the hardware/software tools used. At first I tried a software called serial port monitor and the hardware was a max232 ttl<->rs232 transceiver.

Now I use a 2 resistor based rs232 adapter and the serial communicator software built into MicroCode Studio.
What I found is that now I can see the noise!!! There is a lot of junk along with correct data. Maybe the other software/hardware configuration were filtering that noise so I could only see correct data...

So I thought that adding more preamble could be an initial solution... it worked!
I will try the reliability of the communcation at longer distance to see if I need to add manchester routines...