From: furnish@ccwf.cc.utexas.edu (Geoffrey Furnish) Subject: Re: High speed modems Date: 26 Sep 1992 03:44:02 GMT
In article <68515@hydra.gatech.EDU> gt5584e@prism.gatech.EDU
(Edward Deering Boykin) writes:
>I have a gateway telepath(the new one that works) modem. In order to
>use it with linux , or should I say can I use it with linux? I see
>peaple writing about having 16550 uarts and stuff like that. What
>is that stuff?!? Am I s.o.l. without
>it? Thanks
I would like to know about this too, if anyone has answers. I called
Gateway and they tell me the Telepath uses the "Dual 450" chip, not
a 16550.
In any event, I would sure like to here from someone who _actually_ knows
what they're talking about when it comes to serial comm under LInux.
All this talk about how there's no way you can expect to do high speed
comm under unix without losing characters is bull, I am sure of it.
OS/2 does reliable serial comm up to 115 kilobaud. I can do 19200 under
OS/2 on a 386sx-16 with a 16450 WITHOUT _EVER_ LOSING A SINGLE CHAR. It
is b/c of one thing: Hardware Handshaking. Under OS/2 I tell OS/2 with
the mode command that I want to use cts/rts handshaking. Then I tell the
modem, and that's all there is to it--I never drop a char.
Now I'm not going to say the _throughput_ is always that high. That, after
all, is the whole point of handshaking. If the computer can't keep up
for some reason, the flow is stemmed momentarily, etc. But I can set the
modem for 19200, and never worry that I'm going to lose characters.
I sure would like to be able to do this under Linux--and I know darn well
it doesn't depend on having a 16550. The FIFO buffer in the 16550 may help
out a lot in terms of reducing interupt frequency, etc, I believe that,
but I know it is possible to do reliable high speed comm if you use hardware
handshaking. OS/2 does it, therefore surely Linux could do it, no?
Anyone who actually knows about this matter under Linux, please speak up.
Tons of us out there would like to know the hard facts, not just more
of this silly speculation which has been the majority of this thread so
far.
Geoff Furnish
furnish@dino.ph.utexas.edu