serial printers under microport 386

[Keith Hankin]

In article <2712 at quacky.mips.COM> menna at mips.COM (Randy Menna) writes:
|I am having some trouble getting serial printers to work under
|microport 386.  I have a compac 386 running 2.2, with 16 computone
|serial ports.  These ports work great when connected to a terminal,
|but I am unable to get them to talk to a serial printer (panisonic 1090i).
|
|I turned off the getty for the port attached to the printer, and I did
|a "lpadmin" to configure that port as "lp1", this seemed to work ok.
|However, lpstat claims files are being printed but nothing comes out
|of the printer.  Also I do not get output when I do a "cat" to that
|device.
|
|I thought that this meant that the electrical signals weren't correct,
|but if I put a getty on that port, then it prints "login" on the printer,
|and files can also be "cat"ed to the printer.
|

The reason the "cat" was not working for you without the getty is because
the default communications parameters for opening the serial device did
not match those of your terminal.  In particular, the default baud rate
is 300 without a getty on the port.  The proper way to cat to the device
without a getty is to type "(stty 1200 0<&1; cat FILE) >/dev/tty??",
assuming your printer is at 1200 baud.  This is also probably why you
cannot get the printer working properly.  You should be using the prx,
dumb or serial model (-m option to lpadmin) for a serial printer.  In
addition, you need to check the interface file in /usr/spool/lp/interface
to make sure that the proper communications parameters (including baud
rate) are set with an "stty" command.

-- 
Keith Hankin	keith at uport
Microport Systems