[lug] pppd w/ external model

[Matt Clauson]

On Saturday 27 October 2001 15:56, you wrote:
>    I attached an external "28,800 FAX" modem to my Compaq Presario,
> believing the internal modem to be windows-only (?)

Heh.  Most likely, it is.  Do you have a chipset for us to go by?

>   By changing the pppd parameter to /dev/ttyS0, I made the light on
> the external modem come on, and I didn't get that "config script
> failed" message for a change, but it just hangs at that point. I
> tried changing the speed parameter to 28800. pppd says "28800 not
> supported". Maybe I need an external 57600  modem or 38400, since
> pppd doesn't seem to support any other speeds ?

*laugh* Now this is a question I never expected to see.  The 38400 or 
57600 is the data rate between the modem and the computer, not between 
modems.  The data rate is also in pretty much fixed increments...  
Common data rates that you will see presently are 9600, 19200, 38400, 
57600, and 115200.[1]  Your problem is that Linux doesn't recognize 
28800 as a DTE datarate, since it only has fixed increments in the 
kernel, and, if memory serves, controls the port speed by ioctl(2).

Go ahead and leave the data rate set at 38400.  It won't hurt anything, 
and it'll make things work.

And please excuse my laughter.  I didn't expect to see this particular 
question on the list...  Just brought a good smile to the day.

--mec

[1] Some historical values you will see (and most likely associate with 
DCE, such as modems) are 300, 600 (both very rarely), 1200, 2400, 4800, 
and 7200 (also very rarely).  If you want, I can go into a bit greater 
detail.