Steve Forrette <forrette@cory.berkeley.edu> (06/04/91)
I hope that someone familiar with PC Pursuit or MNP-compatible modems in general can help me with this one: I need to know how to tell an MNP-compatible modem to pretend that it doesn't have MNP, so that when it calls out and reaches another MNP modem, it will "play dumb" and not enable MNP mode. In other words, the connection will be a standard 2400 baud connection. Presumably, this is done with an ATS command on the dialing end, prior to the dialing command. My situation is that I'm dialing into Telenet using a standard 2400 baud modem. The outdial modem in the remote city is dialing to an MNP (I think 5) modem, and returning a "CONNECT 2400 EC", indicating an MNP connection. The problem is that if the remote host sends data continuously for more than a screen or so, there is tremendous data corruption and loss. When the remote modems connect in standard, non-MNP mode, everything works dandy. The Customer Service people at Telenet were of no help - they couldn't quite understand the problem, and said that the only valid commands to give an outdial modem were ATZ and ATDT. I suspect that some other commands, such as ATS might work as well, but they would not tell me about them. Anyone have an answer? Thanks! Steve Forrette, forrette@cory.berkeley.edu
erhall@labrea.stanford.edu (06/07/91)
Steve Forrette <forrette@cory.berkeley.edu> writes: > I need to know how to tell an MNP-compatible modem to pretend that it > doesn't have MNP, so that when it calls out and reaches another MNP > modem, it will "play dumb" and not enable MNP mode. In other words, > the connection will be a standard 2400 baud connection. [Describes problems when Outdial modem connects with MNP enabled.] > The Customer Service people at Telenet were of no help - they couldn't > quite understand the problem, and said that the only valid commands to > give an outdial modem were ATZ and ATDT. The PC Pursuit people should have known this one. The following is from one of the help files available on their own Net Exchange support BBS (from the '@' prompt, do a "c pursuit" to access it): "To modify MNP setting in the Hayes command mode: AT*E0 No MNP AT*E1 Auto MNP AT*E2 Force MNP (call will fail if MNP unavailable)" The ATZ command will reset the Outdial modem to default settings, including disabling of its MNP4 capability. It's wise to do that as soon as you connect to it, then enable MNP with AT*E1 if you want. The problem you're experiencing (with garbled data when MNP is enabled) seems to be caused by incorrect flow-control at the far end. Some BBSes I call work fine (EXEC-PC, for instance), while others (Channel1, in Boston, included) seem to ignore requests from SprintNet's side to stop sending data. If they continue to send, SprintNet's X.25 network has no choice but to throw away packets of data. I keep track of which ones don't work properly and don't enable MNP for those calls. Earl Hall | via PeaceNet: | GEnie: ERHALL Chicago IL | cdp!erhall@labrea.stanford.edu | +1 312 685 9735
schuster@cmcl2.nyu.edu> (06/08/91)
In article <telecom11.429.9@eecs.nwu.edu> forrette@cory.berkeley.edu (Steve Forrette) writes: > I need to know how to tell an MNP-compatible modem to pretend that it > doesn't have MNP, so that when it calls out and reaches another MNP > modem, it will "play dumb" and not enable MNP mode. In other words, > the connection will be a standard 2400 baud connection. There are two possible ways to do this. One is from Racal mode (enter control-E then <ENTER> after an ATZ; enter I [idle] to return to Hayes mode). I'll spare you the details, since there seems to be a security block now which prevents you form altering the option tables in Racal mode (PHOOEY!!) On my RV 2400VP you also could toggle the EC from Hayes mode using the AT*En command, where (if I remember correctly) n=0 disabled error correction n=1 allowed for error correction with fallback to "vanilla" mode n=2 disconnected if EC mode could not be negotiated. These are different modems, so the options might be different. Try a few. But AT*E0 might just do the trick for you. Mike Schuster | -CIS: 70346,1745 -NY Public Access UNIX: schuster@panix.com | -MCI Mail, GENIE: -The Portal (R) System: schuster@cup.portal.com | MSCHUSTER
David Lemson <lemson@ux1.cso.uiuc.edu> (06/09/91)
forrette@cory.berkeley.edu (Steve Forrette) writes: > quite understand the problem, and said that the only valid commands to > give an outdial modem were ATZ and ATDT. I suspect that some other > commands, such as ATS might work as well, but they would not tell me > about them. Unfortunately, I haven't had PC Pursuit for a while, and don't still have all of my lists of commands, but I can tell you that all of the outdial modems are Racal-Vadic modems, so if anyone can look up the command for disabling MNP on a Racal-Vadic modem, that's what you need. I have a more Hayes-ish modem that needs AT&E0 to disable MNP, but I doubt that will work for you. David Lemson University of Illinois Computing Services Consultant Internet : lemson@uiuc.edu UUCP :...!uiucuxc!uiucux1!lemson