Xref: utzoo comp.sys.next:12976 comp.sys.hp:7738 comp.lang.postscript:7615
Path: utzoo!telly!eci386!ecicrl!clewis
From: clewis@ferret.ocunix.on.ca (Chris Lewis)
Newsgroups: comp.sys.next,comp.sys.hp,comp.lang.postscript
Subject: Re: HP LJ III dying under NeXTStep 2.0
Message-ID: <1363@ecicrl.ocunix.on.ca>
Date: 18 Feb 91 16:10:16 GMT
References: <1991Feb15.031524.3210@wam.umd.edu> <1991Feb15.171041.3582@chinet.chi.il.us>
Followup-To: comp.sys.next
Distribution: na
Organization: Elegant Communications Inc., Ottawa, Canada
Lines: 57

In article <1991Feb15.171041.3582@chinet.chi.il.us> les@chinet.chi.il.us (Leslie Mikesell) writes:
>In article <1991Feb15.031524.3210@wam.umd.edu> mikec@wam.umd.edu (Michael D. Callaghan) writes:

>>Ever since I upgraded my NeXTCube 030 to NeXTStep 2.0, my HP
>>Laserjet III PostScript doesn't work right.

>>I am constantly getting I/O Config errors when printing Complex PostScript
>>files. If I try to reset the printer, I proceed to get PS Error 18, which
>>says a non-postscript operator has been used. 

>If the postscript generates any output back to the sending tty, it is
>important to have the spooler port configured properly to handle it.

>I had a problem with more or less random timeouts and hangups which
>turned out to be caused by the print spooler enabling reverse xon/xoff
>flow control on the line (i.e the computer could send the printer an
>xoff for flow control on messages coming back).  Nothing on the
>computer was ever reading from the printer, so after a printout or
>two that generated output (usually psroff), the computer would send
			   ---------------
(mine or Adobe's?  By default, psroff emits a fair bit of stuff back
up the line unless you define NOCHATTER, and anything wrong with handshaking
will show up quickly)

>an xoff and the printer would sit waiting to be able to finish sending
>back its message.

>Another posting recently pointed out a similar but more drastic problem
>when character echoing is enabled on the line.  That could be your
>trouble as well.

Many people using Postscript printers are unaware of the fact that Postscript
prints error messages and so-on "back up the line".

When people start having problems, whether it be sporadic hangups, or
when you're trying to debug your hand-written Postscript, or you're
trying to configure psroff (;-) it really pays to see what the printer is
saying.  For a printer on a serial port, you just start up a cat reading from
the serial port.  Eg: if your printer is on port /dev/ttyA, just type:

	cat /dev/ttyA&

And then you'll see everything the printer has to say about your
print jobs.  For example, psroff uploads stuff about how many pages
were printed and other miscellaneous things - if you run:

	cat /dev/ttyA > somewhere

You can keep a printer log with the real page count.

You can use this feature for all sorts of things, including having the
printer tell you how wide all the characters are.
-- 
Chris Lewis, Phone: (613) 832-0541, Internet: clewis@ferret.ocunix.on.ca
UUCP: uunet!mitel!cunews!latour!ecicrl!clewis; Ferret Mailing List:
(ferret-request@eci386); Psroff (not Adobe Transcript) enquiries:
psroff-request@eci386, current patchlevel is *7*.