Xref: utzoo comp.sys.att:2613 comp.unix.questions:5833 Path: utzoo!mnetor!uunet!vsi!friedl From: friedl@vsi.UUCP (Stephen J. Friedl) Newsgroups: comp.sys.att,comp.unix.questions Subject: Re: Hayes modem for 3B2 Message-ID: <52@vsi.UUCP> Date: 26 Feb 88 05:53:13 GMT References: <449@stech.UUCP> <220@mccc.UUCP> <2765@chinet.UUCP> Organization: V-Systems, Inc. -- Santa Ana, CA Lines: 69 Summary: in+out on a 3B2 Hayes modem *WORKS* In article <2765@chinet.UUCP>, randy@chinet.UUCP (Randy Suess) writes: > This was discussed at length a while ago. The problem is that the Hayes > compatible modems do not handle CD and DTR properly, so that you > cannot get a 3b2 to dial out AND have the hayes drop and raise CD > properly for dial-in. There are modems that work with the 3b2, and > there is a hardware hack to make the hayes work. Those of you with 3B2s running System V Release 3.1 should look in your 3.1 Release notes on page 2-67 under "Basic Networking Utilities: Intelligent Modems". AT&T has made Hayes go in+out on the same line with carrier detect working the right way. What the heck, I'll include a copy of the text: [------------------begin Software Notes--------------------] *Basic Networking Utilities: Intelligent Modems* Features have been added to the /usr/lib/uucp/Dialers and /usr/lib/uucp/Devices files to prevent problems that occur when using System 75s, System 85s, Hayes-compatible modems, and other intelligent modems that do not keep Carrier Detect high all the time [guess which of the above actually kicked off the fix :-) ]. Devices Adding a ,M to the second field of an entry in the Devices file will cause the O_NDELAY flag to be set when the device is opened. This prevents BNU soft- ware from blocking on the device while waiting for a CD. The example below shows how to add the ,M to a Devices file entry for a devices connected to an automatic call unit for a Hayes modem. ACU tty11,M - 1200 hayes \T Dialers Adding \M before the chat script in a Dialers file entry will set CLOCAL, preventing any change in the CD lead from resetting the the state of the device [prevents SIGHUP - SJF]. Once the conversation has been established, \m will clear CLOCAL. This will allow BNU to again monitor changes in CD (for exam- ple, to notice if the line drops). The example below shows how tyo add \M and \m to an entry made for a Hayes modem in the Dialers file hayes "=,-," "" \M\dAT\r\c OK\r \EATDT\T\r\c CONNECT \m\c +----+ |NOTE| For some devices, adding a \p after the \M may +-+--+ be necessary. | | [end of Software Notes] For a long time we had troubles with this: the outgoing call would not work unless cu or uucico debug mode was on. "cu -d 911" worked fine but "cu 911" did not. Tonight while writing a previous note on this topic I rediscovered the |NOTE| above, ad- ded \p to my scripts and it works great. This information only appears (to my knowledge) in this one place in the Release Notes, and it was not there in Release 3.0. Good luck, Steve -- Life : Stephen J. Friedl @ V-Systems, Inc/Santa Ana, CA *Hi Mom* CSNet: friedl%vsi.uucp@kent.edu ARPA: friedl%vsi.uucp@uunet.uu.net uucp : {kentvax, uunet, attmail, ihnp4!amdcad!uport}!vsi!friedl