Has anybody implemnented 232 or 485 comms at 9600 baud without using
error correction and had no problem. With my problem stated below,  I
have tried changing the crystals that i was using but i stiil had the
same problem. I've finally cured my comms problem by  implementing error
correction using a checksum but that still doesn't explain why it would
work properly without it. Any suggestions?

Regards
Stuart




> Hello everyone, I have some problems with my RS485 network and I'm
> hoping someone could shed some light on them. My setup at the moment is
> a simstick with a 16c84 running at 4Mhz as a slave, I have another setup
> as the master. The master receives commands from my PC via the RS232
> port and then proceeds to send them down the RS485 network to the slave,
> the slave receives the commands and does what it should and then sends
> back some data as a reply. Around 70% of the time the data that is
> returned as a reply is corrupt, but the slave executes the commands sent
> to it ok. I'm using the LT1487 chips that were used in the Nuts n Volts
> example and I'm running it at 9600baud, Ive just discovered if i lower
> the speed right down to 300 baud it functions fine , Any suggestions ?
> (if it was the crystal you would expect it to have errors on receiving
> as well as txing, wouldn't you?)
> The other problem i am having with this network is if i put the 120r
> terminating resistors on, the network it sends no data at all (put a cro
> on it and you get a flat line) but without the resistors you get
> beautiful square waves
>
> Thanks for your help
> Stuart
>
> P.S. I'm using Pic Basic Pro
>