jtn@ADS.COM (John T. Nelson) (11/21/90)
I'm currently having big problemtrying to talk to other computers with my Mac IIcx and Racal Vadic 9632 VP V.32 modem. Someone on the net mentioned that the problem with high speed communications and the Mac is that there just aren't enough control lines... i.e. you cannot use hardware flow control on the Mac serial ports. This seems unlikely since Apple does provide lines "Handshake In and Handshake Out" on the serial port, although the exact meaning of these names is quite vague. Question: Can I use the Mac with my high speed (9600 bps) modem? Can the Mac IIcx support hardware flow control? WHAT ARE THE EXACT PINOUTS OF THE CABLE I NEED and how should I configure the Mac and modem to make them talk with erach other properly? I have no problem swith 2400 bps communications. When I take it up to the high speeds, nothing works. Thanks guys! -- ORGANIZATION: Advanced Decision Systems GEOGRAPHIC: Arlington, VA UUCP: kzin!speaker@mimsy.umd.edu INTERNET: jtn@potomac.ads.com SPOKEN: John T. Nelson PHONE: (703) 243-1611 PROJECT: Macintosh hacking -- "Love the Machine... Hate the Company"
merlyn@digibd.com (Brian Westley (Merlyn LeRoy)) (11/26/90)
jtn@ADS.COM (John T. Nelson) writes: >.. Someone on the net >mentioned that the problem with high speed communications and the Mac >is that there just aren't enough control lines... i.e. you cannot use >hardware flow control on the Mac serial ports. This seems unlikely >since Apple does provide lines "Handshake In and Handshake Out" on the >serial port, although the exact meaning of these names is quite vague. The Mac serial ports supply exactly one hardware input and one hardware output, "CTS" and "DTR", repectively. The hardware input line, "CTS", is variously used as CTS (hardware flow control), DCD (carrier detect when connected to a modem), or external clock. If your software package insists that "CTS" be used as carrier detect and won't allow you to use it for hardware flow control, you can't use it for hardware flow control. If you use "CTS" for hardware flow control, it's going to be difficult to determine the state of carrier detect (but chatty modems can help). You can use it for one thing at a time; you can't use it for two different things simultaneously, like CTS & DCD. ---- Brian Westley DigiBoard