CTS/RTS hardware handshake for GS Mini-Din 8 DB-25 (RS-232 Male) Female Male 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 8 7 6 6 7 8 5 4 3 3 4 5 DB-25 (RS-232 Female) 2 1 1 2 13 12 11 10 09 08 07 06 05 04 03 02 01 25 24 23 22 21 20 19 18 17 16 15 14 DIN-8 DB-25 Signal Discription 3 2 TD (Transmit Data) 5 3 RD (Receive Data) 4,8 7 GND (Ground) 2 5 CTS (Clear to Send) 1 4,20 RTS (Ready to Send) (20 = Data Terminal Ready, DTR) 7 8 DCD (Data Carrier Dectect) The wiring for a GS-serial-port and a modem,is as follows: GS serial port Modem 1....>>...........DTR..............20 2.................DSR......<<.......6 3....>>...........TxD...............2 4.................GND...............7 5.................RxD......<<.......3 7.................DCD......<<.......8 1.The arrows mark the direction of the signal (i.e,DTR is output from the modem into the computer etc,). 2.The numbers for on the GS port column assume the following numbering on the connector: +++# #+++ + #__# + + 8 7 6 + + + + 5 4 3 + + + + 2 1 + ### ### +# #+ ++++ 3.The numbers on the modem column assume the standart DB-25 RS232 connector. As to 'minimal connection',I don't think there are many modems that would compromise on DTR.Anyhow,lack of DSR and DCD is usualy more tolerable. TxD+/TxD- and RxD+/RxD- is part of the glorious RS 422 concept,and more accurately,of a method called 'differencial signal'.In this method,for each of the Receive and Transmit signals,one wire carries the signal just as it would on RS 232,and a second wire carries the first's inverse polarity.(Thus the couples xD+/xD-).Now,the receiving device compares the xD+ to it's inversed partner.If xD+ is higher than xD-,the receiving device reads 'high', if it's lower,the device reads 'low'.What you get is a speed considerably higher than on RS 232,and a connection much more emmune to noises. You'll have to work out the appropriate Control-Panel configuration according to the modem and software you use. Yoram Ney Hebrew University,Jerusalem Bitnet:NEY7@HBUNOS From pro-freedom!pro-ren!pro-applejacks!terry%clark.edu@mail4.engin.umich.edu Wed Jun 16 05:21:23 1993 Received: from srvr2.engin.umich.edu by mail4.engin.umich.edu (5.64/1.35) id 6090306cf.0017b7e; Wed, 16 Jun 93 05:21:19 -0400 Received: from crash.cts.com by srvr2.engin.umich.edu (5.64/1.35) id AA18626; Wed, 16 Jun 93 05:21:16 -0400 Received: from clark.edu by crash.cts.com with smtp (Smail3.1.28.1 #15) id m0o5tg8-00005wC; Wed, 16 Jun 93 02:21 PDT Received: by clark.edu (Smail3.1.28.1 #1) id m0o5tcF-0000ZBC; Wed, 16 Jun 93 02:17 PDT Received: by pro-freedom.van.wa.us (sendmail 2.3.1 7jun93) id ; Wed, 16 Jun 93 02:03 PDT Received: by pro-ren.cts.com (sendmail 2.3 24mar92) id ; Wed, 16 Jun 93 02:46 CDT Received: by pro-applejacks.cts.com (sendmail 2.3 24mar92) id ; Tue, 15 Jun 93 21:56 CDT Message-Id: Date: Tue, 15 Jun 93 21:48:44 CDT From: terry@pro-applejacks.cts.com (Terry DeSmet) X-Mailer: Mail (1.7 20feb92) To: dmag@engin.umich.edu Subject: Re: FAQ/IWII with PC Status: R I'm interested in using my IWII on a pc clone because I have a GS *and* a PC. I'd also like to use my Panasonic 2123 printer with the GS, so I'd like a diagram of the best way to hook up a PC and a GS and share the printers. I have the PT3 manual, and it tells the pinouts for a cable, but I don't want to get into the cable construction business. I want to buy one that I KNOW will work before I order it. I don't remember what all I said in my previous mail, but I've heard that a Mac modem cable will work, and also that it WON'T work with a GS. Here's a couple of messages I saved concerning the wiring. CS-ID: #7206.apple/apple.corp@pro-applejacks, 2907 chars Date: 23 Feb 92 12:23:32 GMT From: t.captain@bluemoon.rn.com (Tc Wilson) Subject: Re: IIGS Hardare Handshaking Serial Cables - Organization: Blue Moon BBS ((614) 868-998[024]) > Does anyone out there in Net.Land have the pin connections to use for a > CTS/RTS handshake compatible serial cable for the GS? [Note: the file assumes an USR is in use, but any flow-control-compatible modem will work - you may have to add commands to the init string in order to TELL the modem that it can now flow-control] In your ControlPanel, you MUST have Modem: DSR/DTR Handshake to YES (the checkmarked default). Otherwise, the firmware will NOT flow-control the modem, and the end user will get stomped on once the 1.5k buffer in the USR fills. Now, for the cable. The following pins must be connected in the WAY THAT THIS SAYS for this to work. This is the NORMAL setup for MOST "Mac" modem cables, minus the carrier detect. GS side: RS232 side: 1 (HSKo) 4 (RTS) 2 (HSKi) 5 (CTS) 3 (TxD-) 2 (TD) 4 (SG) 7 (SG) 5 (RxD-) 3 (RD) 6 (TxD+) 7 (GPi) 8 (CD) -or- 6 (DSR), depending on modem 8 (RxD+) Now, if you don't have the correct cable, my suggestion is this: Go to Radio Shack, and spend $9.95 for a RS232 JUMPER BOX (part #276-1403). This little doodad will allow you to re-wire the connections between the modem and the plug on the end of the cable (thus, re-wiring the cable). MUCH easier than slicing and dicing the cable. CS-ID: #7228.apple/apple.corp@pro-applejacks, 1533 chars Date: Sun, 23 Feb 1992 02:23:00 -0500 From: White.Wolf@f438.n109.z1.fidonet.org (White Wolf) Subject: IIGS Hardare Handshaking Newsgroups: comp.sys.apple2 Message-ID: <698936427.F00001@blkcat.UUCP> Sender: Uucp@blkcat.UUCP CM| Does anyone out there in Net.Land have the pin connections to use CM| for a CTS/RTS handshake compatible serial cable for the GS? I am CM| currently using one that I hacked together based on the diagram in CM| the Hardware Ref. for the GS, but some programs tend to barf quite CM| badly on it, 'cause it doesn't support the hardware handshakes. Males have pins, Females have holes Mini-Din 8 DB-25 (RS-232 Male) Female Male 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 8 7 6 6 7 8 5 4 3 3 4 5 DB-25 (RS-232 Female) 2 1 1 2 13 12 11 10 09 08 07 06 05 04 03 02 01 25 24 23 22 21 20 19 18 17 16 15 14 DIN-8 DB-25 Signal Discription 3 2 TD (Transmit Data) 5 3 RD (Receive Data) 4,8 7 GND (Ground) 2 5 CTS (Clear to Send) 1 4,20 RTS (Ready to Send) (20 = Data Terminal Ready, DTR) 7 8 DCD (Data Carrier Detect) -------------------------------------- ProLine: terry@pro-applejacks Internet: terry@pro-applejacks.cts.com UUCP: crash!pro-applejacks!terry