On Thu, 11 Dec 1997 dillema@acm.org wrote:

> 
> Somewhere in the include files I found 230400 Bps as a standard terminal
> speed, it is however not accepted by stty or pppd. I noticed that the speed
> in termios.h is represented with an unsigned int value. Does this mean max.
> serial speed is 65565 Bps??? If so, I find it a bit strange that 115200 Bps 
> is accepted just fine, while 230400 is not... I'm just being curious here. 
> Could somebody enlighted me on this topic? I may be a bit naive on these 
> things... Would it be a lot of work (and/or generate a lot of problems) to
> switch from integer to long to support the fast serial lines (thinking of 
> ISDN-modems attached to serial ports here and such).

I thought all ports had 32-bit ints, so the max bps is outrageously high.
Also, stty and pppd should be defering to the serial driver to decide if a
baud rate is acceptable. Exactly where things stop depends on the serial
driver. In a machine with different types of serial drivers, the max rate
could varry from port to port.

Take care,

Bill