[mdlug] Semi-OT: Serial modem behavior

[Brian Brodsky]

Ray,

You could try ate1 and hit enter (maybe echo is off). You could also try 
at&f and hit enter to try to set modem back to factory setting and maybe 
ate1 and hit enter after that.

Brian

On 07/24/2014 11:32 AM, Jeff Hanson wrote:
> Try 7E1.  115K is generally the max for RS-232 modems since faster UARTs
> weren't common until later eras.
>
> I played around with an old system like that several years ago.  The
> problem I had was its 166MHz Cyrix 6x86 CPU which X wouldn't work with  (on
> Puppy Lite, IIRC).  I had to use TinyX but only one version worked and no
> 3D.  I found that ISA sound cards weren't fast enough for MP3s so I had to
> use a PCI card but even that could only support 24K MP3 streams.  I was
> lucky and had a 56K v.90 USR ISA modem with a controller and it acted as a
> serial port.  The only graphical web browsers that were usable was the
> embedded version of Konqueror and maybe Dillo.
>
>
> On Thu, Jul 24, 2014 at 8:42 AM, Ingles, Raymond <
> Raymond.Ingles at compuware.com> wrote:
>
>> I have access to three serial modems, all different models. One of them
>> works just fine - a USR Sportster. The other two (a Zoom 2400 baud, and
>> another 14.4 modem whose manufacturer escapes me for the moment) display
>> the same problem - no data coming back from the modem to the computer.
>>
>> Cabling doesn't seem to be the issue; the same cables work with one modem,
>> but not the other two. I've used a couple different cables, and used both
>> USB-to-serial adapters and on-motherboard serial ports.
>>
>> The behavior on the two problem modems is the same. Using a program like
>> 'minicom' or 'gtkterm', I can see the modem notice things like DTR and such
>> - the appropriate lights turn on. When I send AT commands, I can see the RD
>> and even SD lights blink. Yet absolutely no response shows up in the
>> terminal. On the working modem, I get responses without issue. But on the
>> failing ones, nada.
>>
>> I've tried bauds from 300 to 115200. (At higher bauds, the non-working
>> modems RD and SD lights stop blinking.) I've pretty much stuck with 8N1
>> parity, but if anyone has suggestions for alternatives there I'm curious.
>>
>> Obviously the use cases for serial modems are... pretty rare these days.
>> But I've got this 'dream machine from 1993' that I occasionally bring out,
>> and a functional serial modem would be a lovely thing.
>>
>> The contents of this e-mail are intended for the named addressee only. It
>> contains information that may be confidential. Unless you are the named
>> addressee or an authorized designee, you may not copy or use it, or
>> disclose it to anyone else. If you received it in error please notify us
>> immediately and then destroy it
>> _______________________________________________
>> mdlug mailing list
>> mdlug at mdlug.org
>> http://mdlug.org/mailman/listinfo/mdlug
>>
> _______________________________________________
> mdlug mailing list
> mdlug at mdlug.org
> http://mdlug.org/mailman/listinfo/mdlug