[Info-vax] Programming the serial port on an Alphaserver 200

[rtk]

Ok, first, thanks for all the many helpful comments!

I got things to the point where I can send bytes out the port with a
simple C program using fopen() and fputc().  The string I send out is
preceded by a 0x0A, however.  When I try to read bytes sent to the
port the program hangs.  If I look at the output of SHOW DEVICE/FULL
_TT it shows TTB0 as using formatted I/O which is not what I want.
Also, I haven't found how to open the port for reading and writing at
the same time.

My goal is to use the Alpha to mimic a hardware device so I can debug
the commands that are sent to it.  Ie, I want to see the data packets
that the host computer is sending out.  Normally, I use Forth on an
Apple II for this stuff or Python on a Linux box.  If I can't open the
TTB0: port for reading and writing of single bytes it won't do what I
want and I can't justify spending lots of time learning how to
configure something for such a simple purpose when I already have
other tools that will do what I want.  I just thought it would be fun
to use the old box for this task.

Ron