Path: utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!sdd.hp.com!hp-pcd!hpfcso!rjn
From: rjn@hpfcso.HP.COM (Bob Niland)
Newsgroups: comp.sys.hp
Subject: Re: Serial Line drivers on HP9000/375
Message-ID: <7370244@hpfcso.HP.COM>
Date: 31 Oct 90 15:41:02 GMT
References: <1133@skye.cs.ed.ac.uk>
Organization: Hewlett-Packard/FSY Ft.Collins,CO,USA
Lines: 22

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  You need a newer version of the serial port driver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