plw@mgweed.UUCP (Pete Wilson) (11/09/84)
(*) Unix is a trademark of AT&T Bell Labs I have an Onyx C8002M running System III. I would like to use an autodialing modem for cu, uucp, and as a dialup. A small problem arises when attempting to initialize the autodialer for cu/uucp. As I understand it, the tty drivers require the DCD lead (Data Carrier Detect) to be asserted before writing to the device. With the two modems I've tried, the only way to get DCD asserted is either to actually have carrier (as in autoanswering) or to physically change an option switch to have DCD follow DTR (Data Terminal Ready). Changing the option switch is OK, IF all the modem is going to be used for is dialing out. However, when /etc/getty is started on the port and DCD is asserted, the 'login' message is sent to the device. Autodialing modems vary on how they respond to a 'login' message. The solution here is to set the option for DCD to respond to carrier. That's OK too, IF all the modem is used for is answering dialins. Has anyone out there solved this problem? If so, I would be definitely interested in how it was accomplished! The machine has only one port with modem control, and I'm not too wild about installing another telephone line and modem, even if I could! I don't have a source license, so hacking the code isn't possible. It seems to me that using modems with integral autodialers would be a problem with Unix(*). Even if enough ports and telephone lines are available, the modem and autodialer both communicate through the same connector on the modem. Possibly I'm missing something here...... Pete Wilson ..!ihnp4!mgnetp!mgweed!plw