Tjaart, regarding your schematic:

> It converts +-12V (on the PC side) to -+5V (note the
> inversion) on the micro side.

Doesn't it convert +-12v to 0v-5v, unless RTS goes negative in which case
the PIC sees -12v?

Could you tie the ground connection to pin 4 instead of pin 5 to get the
legal voltage swing for transmitting to the PC?  (I mean if you adjusted the
R values, set the control lines correctly at the PC end and go through
diodes just in case).

Thanks for the info,

Bruce Cannon
Style Management Systems
1228 Ceres ST Crockett CA 94525
(510) 787-6870
http://www.jps.net/bcannon

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