Path: utzoo!telecom-request Date: Wed, 5 Jun 1991 03:41:54 -0400 From: Jamie Mason Newsgroups: comp.dcom.telecom Subject: Re: Pet Peeve About Newer Modems (was Telephone Keypads) Message-ID: Organization: University of Toronto Computer Services Advisor Sender: Telecom@eecs.nwu.edu 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 426, Message 1 of 10 Lines: 67 In article forrette@cory.berkeley.edu (Steve Forrette) writes: > This reminds me of a "pet peeve" (sic?) that I have with the newer > modems. Both the Hayes 9600 V-series and the $74 2400 card-modem I > have won't accept an ATS11 value (DTMF duration) of less than 50ms. > The default seems to be 100ms. The Hayes will take a smaller value, > but use 50 during tone generation. The clone returns ERROR for a > value less than 50. The old 1200 geniune Hayes that I have will take > values down to 1ms, and actually do it as well. The default on my modem (an old USRobotics "VARmodem" 2400 internal) for the tone generation is 70ms. 70ms is obnoxiously slow, as it is. *How* can they set their *fastest* speed to 50? I guess it is like those databases which try to get smart about names, and inevitably end up mangling esoteric names; you know a little more about your CO switch than the modem, but the modem won't give you the benefit of the doubt. My modem, like your old 1200, will go right down to 1ms, but the 1ms is a pretty feeble attempt at DTMF. > [Moderator's Note: And while Toby is answering that, here is another > question: how come US Robotics has a condition you can set which > allows for 'quick dialing', or dialing without waiting the obligitory > two seconds before starting? Hayes used to claim (maybe still do) > that telco tariffs require a two second pause before dialing. You > could not set that particular S-register less than 2. Telebit seems > to feel the same way ... but USR lets you go off hook and bang those > digits right out if you set the register for it. PAT] What S-Register is that? I know how to set my tone-generation rate really fast, but I don't see an S-register which controls how long my modem waits between taking the phone off the hook and dialing. My modem seems to wait for a dialtone before dialing. (Smart, eh?) As for the two second delay, while two seconds is a little long (restrictive) in the usual style of Phone Company tarrifs, *some* delay *is* required. Dialing on my phone, I have to wait about one second before I get the dial tone. I can't dial sooner, or it will miss some digits. Anyone know *why* 35ms (or 36ms) seems to be a universal limit on modern exchanges? Is this designed in? Also, I have heard of, but never heard officially, of a telco tariff which requires that autodialers not retry the same number more than ten0 times in a row automatically. This lead to: a) some crippled terminal programs which won't do more than ten retries before having to be restarted, and b) crippled hardware -- my DUoFone 195 (an old Radio Shack gadget) has an auto redialer which keeps trying till there's no more busy. But it will only try a maximum of ten times. Of course, this is all obsolete now, in the days of Call Return, where the Network does it for you. Jamie [Moderator's Note: Register S-6 in many modems sets the length of time to wait off hook before dialing. In the USR, the command ATX6 overrides the two second delay and dials immediatly. The ten attempt limit is to prevent repeated harassment of people who get wronh number calls intended for modems. Telco's repeat dialing feature won't change this; the modem does not care if it dials 7-D or *66. After ten tries, it will stop dialing. PAT]