On Wed, 12 Nov 1997, Andrew S. Clapp wrote:

>  > 28800 bps is a rate which standard PC com ports don't support.  Try
>  > replacing 28800 with 38400 and see if the behavior improves.
> 
>  I did try that.  I also tried 9600 and 14400.  No good.


You have to understand one thing ... numbers like 14400 and 28800 are
values that no computer has ever trasferred data at.  The interfaces on
those modems don't even have the capability to do those values, much less
your computer.  The modems, every one of them that does better than 9600,
have software in them to change the BPS rate to something that you can
use.  If you try to set your BPS to something crazy like 28800, your
computer reacts like you tried to set it to Tuesday (it won't/can't do
it).  Set it to something greater, and it'll work.  The modems can be
optioned (using command codes) to look for one particular bit rate, but I
just let mine auto-detect.

Most of the modems have compression schemes working, so that the actual
information rate is greater than the modulated bit rate.  I set mine to
57600, many set theirs to 115000, and you do see _some_ of this, depending
on the compressibility of the data you're transferring, and if you don't
have the compression setting disabled.  Look for keywords like "MNP" or
V.42bis on your modem.

Whatever you do, don't use a bogus number like 14400 or 28800.  Those
things are for modem designers _only_.

> 
>  -ASC
> 
> *                                                    *
>     Andrew S. Clapp - clapp@peak.org - WWW Support
> *                                                    *
> 
> 

----------------------------+-----------------------------------------------
Chuck Robey                 | Interests include any kind of voice or data 
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