Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!cs.utexas.edu!natinst!rpp386!woody
From: woody@rpp386.cactus.org (Woodrow Baker)
Newsgroups: comp.lang.postscript
Subject: Re: Real bottleneck 1200 bps on LaserWriter NTII
Summary: serial woes
Message-ID: <17648@rpp386.cactus.org>
Date: 14 Jan 90 01:10:16 GMT
References: <1731.25ae524c@cc.helsinki.fi>
Organization: River Parishes Programming, Plano, TX
Lines: 51

In article <1731.25ae524c@cc.helsinki.fi>, tarkkonen@cc.helsinki.fi writes:
> 
> The programs we use write to the LPT1 port and it is redirected the normal
> way  using: MODE LPT1:=COM2:.
> 
> The LaserWriter NTII owners manual says the serial port should be 
> configured: MODE COM2:9600,N,8,1,P to work at all. This is the way
> my AST TurboLaser/PS manual tells me to configure the port.
> 
> The same programs write perfectly with both serial and parallel ports
> with my AST TurboLaser/PS, here I use mostly the parallel interface,
> but I have tested the programs and procedures I have tried on the
> LaserWriter NTII with the serial interface and they work ok.

I'd be willing to bet that the following is the problem:
MS-DOS machines don't work with XON/XOFF protocol using normal dos redirections.
The problem is that Microsoft DOS, doesn't have the intellegence to know what
it is doing.  It can't input from a paralell port.  There are 2 solutions.
the first one is install AST superspool and let it handle the redirection.
This program is a spooler that can be told about XON/XOFF.  The second
thing is to makesure that your computer printer cable is wired for DTR/DSR.
The cable that I use and appears to work for a QMS-ps810 is symetrical.
What you do to one end, you do to another

2-\__________________/-3
3/-------------------\2 (cross these for XT)
5\----------------------\4
4/-----------------------/5  cross these
6--|
   |
8-----------------------20
Do the same thing on the other end.

You also need to makesure that the laser is set to either xon/xoff or
if you are using superspool, although superspool can handle DTR/DSR as
well.  If you don't want to use superspool, then make sure it is DTR/DSR
and try the above cable.  You'd probably better off to use paralell
if you have it.

Cheers
Woody
p
> Has anybody some knowledge or experience with this Apple printer.
> I have tested several computer with the printer, so I do not believe
> there is anything wrong with the serial port ow the computer. 
> Is this a bug in the computer of the department or is it a feature
> of the Apple LaserWriter NTII?
> 
> Lauri Tarkkonen
> Univeristy of Helsinki
> Finland