[comp.sys.hp] Serial Line drivers on HP9000/375

ajcd@cs.edinburgh.ac.uk (Angus Duggan) (10/30/90)

We are having problems interfacing an HP LaserJet IID printer with an HP
PostScript cartridge to an HP9000/375 workstation, via the RS232 port on the
workstation. The symptoms of the problem are that characters transmitted back
to the workstation are occasionally lost. We've put the printer on a very short
cable to check that it isn't cable length problems, to no effect. We've also
put a serial line protocol analyser on the line to check that the printer is
transmitting the characters, and that the xon/xoff flow control is working
(which it is). I have been using the HP-supplied kermit to communicate with
the printer.

The stty options on the printer line are:
 speed 19200 baud; line = 0; susp <undef>; dsusp <undef>
 intr = DEL; quit = ^\; erase = #; kill = @; swtch = ^@
 eof = ^D; eol = ^@; min = 4; time = 0; stop = ^S; start = ^Q
 -parenb -parodd cs8 -cstopb -hupcl cread -clocal -loblk crts
 ignbrk -brkint ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -iuclc
 ixon -ixany ixoff -ienqak
 -isig -icanon iexten -xcase -echo -echoe -echok -echonl -noflsh
 -opost -olcuc onlcr -ocrnl -onocr -onlret -ofill -ofdel -tostop

Incidentally, does anyone know if HP support Transcript (for BSD spooler
architecture---we're going to be using PLP) on HPUX?

Any information or suggestions gratefully received.

Thanks in advance,
        Angus
==
Angus Duggan, Department of Computer Science,	| I'm pink, therefore I'm Spam.
University of Edinburgh, JCMB,			| JANET:  ajcd@uk.ac.ed.lfcs
The King's Buildings, Mayfield Road,		| VOICE:  (UK) 031 650 5126
Edinburgh, EH9 3JZ, Scotland.	| OR:  ajcd%lfcs.ed.ac.uk@nsfnet-relay.ac.uk

rjn@hpfcso.HP.COM (Bob Niland) (10/31/90)

re: > We are having problems interfacing an HP LaserJet IID printer with an
    > HP PostScript cartridge to an HP9000/375 workstation, via the RS232
    > port on the workstation.

> The symptoms of the problem are that characters transmitted back to
> the workstation are occasionally lost.

The 375 powers up with the serial port set to emulate the older 300 serial
ports, and has the FIFO buffer size set to one byte.  At 9600 bps, inbound
overruns are unavoidable, as the LaserJet can't shut up fast enough when it
sees the Xoff.

The 345 and 375 ports actually have a 16-byte FIFO, as well as CTS/RTS
hardware flow control.  You need a newer version of the serial port driver
(pci.o), which is in release 7.05 and is available for 7.0 and 7.03 through
your local HP support representative.  If they don't have a copy, have them
contact me.

Regards,                                              Hewlett-Packard
Bob Niland                                            3404 East Harmony Road
Internet: rjn@hpfcrjn.FC.HP.COM                       Fort Collins
UUCP: [hplabs|hpu*!hpfcse]!hpfcrjn!rjn                CO          80525-9599