John Waters wrote:

 > I need to monitor the information passing through the RS-232
line of a PC,
 > is there any data tapping device available in the market? Or is
it easy and
 > how to build one?

You may have a look at my AsynMon (DOS),  with a timing
with 0.0001 sec. accuracy. The user-doc tells you the details,
among others how to build a 'tap' cable, which is really simple
if you can handle a solder iron. It is free for private use, see:
   http://www.robh.nl/digsoft.htm#asynmon
I normally requires 2 COM-ports on the monitoring PC,
but if the datatraffic is half-duplex then there is a little device
to use only 1 COM-port (details also documented).
Note: don't be misleaded by the mentioning of modelrailroad
purposes. It really is general purpose, but the provided
data interpretation utilities have some special options for packet
formats used by computer-control modelrailroading systems.

Regards, Rob.

--
Rob Hamerling, Vianen, NL phone +31-347-322822
homepage: http://www.robh.nl/

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads