Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!necntc!ames!sdcsvax!ucbvax!pro-sol.cts.COM!mdavis From: mdavis@pro-sol.cts.COM (Morgan Davis) Newsgroups: comp.sys.apple Subject: IIGS Port Info Message-ID: <8709281120.AA11756@crash.CTS.COM> Date: Mon, 28-Sep-87 05:11:52 EDT Article-I.D.: crash.8709281120.AA11756 Posted: Mon Sep 28 05:11:52 1987 Date-Received: Tue, 29-Sep-87 06:15:33 EDT Sender: daemon@ucbvax.BERKELEY.EDU Reply-To: pnet01!pro-sol!mdavis@nosc.MIL Distribution: world Organization: The ARPA Internet Lines: 42 This is the correct wiring diagram for the Apple IIGS Modem Port cable. Apple is selling a printer cable for use with the modem port and it does not route the correct DCD signal from the modem to the port. This can have bad effects on *smart* software that calls the IIGS serial port firmware to test for carrier status. Here's the correct pinout: Date: Thu, 9 Jul 87 10:08:16 PDT From: bblind (Bruce Lindmark) DB-25 MINI DIN 8 2 <------------------------------< 3 TX- 3 >------------------------------> 5 RX- 6 >------------------------------> 2 DSR (handshake in) 20 <------------------------------< 1 DTR (handshake out) 8 >------------------------------> 7 DCD 7 ------------------------------- 4 SIG GND | -----> 8 RX+ Ground RX+ to prevent noise pick-up RX+ is not needed for RS-232 6 TX+ no connect |_| 6 7 8 3 4 5 1 2 pin locations for male mini din 8 In addition, change the Control Panel settings for the Modem Port as follows: DCD Handshake: No DSR/DTR Handshake: No (the rest of the defaults are fine) --Morgan Davis UUCP: [ ihnp4 cbosgd hplabs!hp-sdd sdcsvax nosc ] !crash!pnet01!pro-sol!mdavis ARPA: crash!pnet01!pro-sol!mdavis@nosc.mil INET: mdavis@pro-sol.cts.com