Problems installing a LaserWriter II

[Ulrich Lauther]

I am trying to install a LaserWriter II on a 286 Compaq running
SCO XENIX SysV 2.2.1 and experience the following situation that I
cannot understand:

The printer has a serial interface, so I use /dev/tty1a.

"cat file /dev/tty1a"
prints the file, so I know the connections and switches are correct.

"lpr file"
lets the printer blink, so I know that the spool-system
accesses the correct port, BUT IT DOES NOT PRINT ANYTHING!

If I substitute "cat $file 2>&1" in the interface-script
with "cat $file > /dev/console, the file appears on the screen, as expected.

If I substitute "cat $file 2>&1" in the interface-script
with "cat $file > /dev/tty1a", nothing happens, other than that the
printer happyly blinks.

(I also tried to stty /dev/tty1a inside the interface-script with the same
parameters that are active when I issue the "cat file > /dev/tty1a" command,
to no avail.)

Any clues would greatly be appreciated.
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Ulrich Lauther               Internet: lauther at janus.berkeley.edu
Siemens / UCB                ph: +1 415 642 3338 fax: 642 2739
				 +1 415 658 8529 home