Hi,

I'm working on a serial to centronics converter using a 16C84 and a
Max232. Handshaking is implemented using the CTS line (may be the RTS
line, I write this at my office, the diagram is at home). The Pic tells
the computer (a Mac in my case) not to send any data when it has things
to do, or when the printer is off-line.
The code I wrote for the Pic does work. If I use a communications
program, all letters types in are printed neatly. If I send data at a
higher rate, things go wrong. Some characters are missing. This in effect
means that handshaking does not work correctly, I think.
CTS goes low alright, and on static tests, the Mac stops moving data when
CTS goes low. STill the actual system does not dunction correctly.

When do I drop CTS? At the end of a byte, during receival of a byte or
what?
I realy don't see what goes wrong. The code to print the received
character is something like 15 cycles max. The rest of the time the Pic
listens to the serial port. Why does it miss chraracters, even if
handshaking does not work?

Can anyone shed some light on this?



Ronald Leenes                                       phone: +31 53 489 42
31
University of Twente                                  fax: +31 53 489 22
55
Dept of Public Administration and Public Policy
r.e.leenes@bsk.utwente.nl

P.O. Box 217, 7500 AE Enschede, the Netherlands