Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!uwm.edu!linac!att!pacbell.com!lll-winken!telecom-request From: hayes!tnixon@uunet.uu.net (Toby Nixon) Newsgroups: comp.dcom.telecom Subject: Re: Can You Disable Call-Waiting AFTER the Call Starts? Message-ID: Date: 25 Mar 91 23:26:48 GMT Sender: Telecom@eecs.nwu.edu Organization: Hayes Microcomputer Products, Norcross, GA Lines: 36 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 241, Message 13 of 13 In article , halcyon!ralphs@sumax. seattleu.edu (Ralph Sims) writes: > Right! S9=20 and S10=20 should keep the modems online even with a > two-second drop in carrier. NOTE: the caveat is that BOTH modems need > to be set up in this manner! Dragging the settings out a bit might be > necessary to do the three +'s, etc. to get the modem back to command > status. Ghads! This stuff can be a Black Art! You're right, it can be a black art -- more than you know. In fact, you don't quite understand S9 and S10 correctly! S9 specifies how long the carrier must be present (either initially, or on recovery after a dropout) before it is recognized by the modem. S10 specifies how long the modem can tolerate carrier to not be present before it hangs up. The measurement of S10 is dependent on S9 -- i.e., if the carrier goes away, it must come back for at least the time specified in S9 BEFORE S10 expires, or the modem hangs up. In your example, the modem wouldn't tolerate a two second dropout; in fact, it would ALWAYS HANG UP on ANY dropout. The maximum dropout which can be tolerated is the _difference_ between S9 and S10. If you want the modem to be able to tolerate a dropout of two seconds, you could, for example, set S9=6 and S10=26. Also, putting the modem into command state with a "+++" does NOT cause carrier to drop. When the modem is in online command state, it is still sending carrier (mark idle). So, there's no need to adjust S9/S10. But as I pointed out in an earlier post, there's no way to dial once carrier is present anyway, so the point is moot. Toby Nixon, Principal Engineer | Voice +1-404-840-9200 Telex 151243420 Hayes Microcomputer Products Inc. | Fax +1-404-447-0178 CIS 70271,404 P.O. Box 105203 | UUCP uunet!hayes!tnixon AT&T !tnixon Atlanta, Georgia 30348 USA | Internet hayes!tnixon@uunet.uu.net