schoenli@ittral.UUCP (Dick Schoenling) (05/25/85)
Greetings, Dimension Owners and Fans! In a previous posting I requested help with getting my Dimension 68000 to talk with a Hayes Smartmodem. Having built my cable according to the documented requirements of the modem and Dimension I was somewhat perplexed with the fact that the modem wouldn't accept any commands although it appeared that characters were arriving at the modem. Most of the suggestions I recieved didn't work, so I came home from work heavily armed with a 'scope and ye olde break-out box. It soon became apparent what the problem was. The documentation was wrong!!!!! The Dimension System Reference Manual cleary states (clearly states) that Pin 5 (CTS) is not uused. False, False, False! Besides that, it ain't true! In order to make the Dimension 68000 serial port talk to the Hayes Smartmodem do the following: Make a straight through cable using only pins 1-8, and 20. (1 and 6 aren't really necessary, but they're usually present on most pre-wired cables) Pin 4(RTS) is definitely high(true,"1"), but pin 5(CTS) isn't but ought to be, as well as pin 20(DTR) which the Hayes manual claims it is set to the forced true state at the factory(also not necessarily true). Therefore, 1-8, and 20 with 4,5,20 shorted together fixes its problems. Now, if I can just figure out the termcap I can see if my corrections in this 'vi' session are there or not. If not, blame it on my admitted ignorance of open mode vi.