TURGUT@TREARN.BITNET (Turgut Kalfaoglu) (01/15/91)
Thanks for the replies on the AT-to-Laptop connection. I was connecting the xmit-to-xmit and receive-to-receive pins together, and no wonder they were not talking to each other. Now I got it, no hw handshaking, just pins 2,3,7.. It works! What a relief! If any of you plan to do the same, beware! 25-pin connector's transmit and receive legs (2 and 3) are INVERSED on the 9-pin connector. So you need to connect 2 to 2, 3 to 3, 7 to 5... -t
andrew@frip.WV.TEK.COM (Andrew Klossner) (01/17/91)
"If any of you plan to do the same, beware! 25-pin connector's
transmit and receive legs (2 and 3) are INVERSED on the 9-pin
connector. So you need to connect 2 to 2, 3 to 3, 7 to 5...
-t"
It may not be inverted. One of your ports is a DCE (modem-like,
usually female jack) and the other is a DTE (terminal-like, usually
male jack). Whenever you want to connect two RS232 ports, the first
thing you have to determine is which are DCE and DTE, and "twist"
accordingly.
This wouldn't be very complicated if manufacturers would rigidly adhere
to the standards for jack sex (DCE always female and DTE always male)
but they don't. A big offender is the Apple Laserwriter and its female
DTE jack, which other manufacturers (such as my employer) feel they
must emulate for compatibility.
-=- Andrew Klossner (uunet!tektronix!frip.WV.TEK!andrew) [UUCP]
(andrew%frip.wv.tek.com@relay.cs.net) [ARPA]