Subject: Re: DeskWriter (was Re: printer / modem)
To: None <j-valdes@uchicago.edu>
From: Bill Studenmund <wrstuden@loki.stanford.edu>
List: port-mac68k
Date: 01/12/1997 16:20:11
> No, I'm using a copy I've compiled (gs 2.6.2) w/ the djet500 driver.
> I thought that the problem might have been the PCL generated by this
> driver, but as I mentioned, the identical PCL file sent to the printer
> from the MacOS side (using ZTerm) prints just fine.  Additionally,
> I've been using the djet500 driver w/ my MacOS version of gs 2.6.2 w/o
> any problem for some time.
> 
> Nevertheless, I'll try your gs binary to see if it helps.  I believe
> you've hacked George Cameron's deskjet driver (cdj*) for proper
> monochrome output for the DeskWriter, and I like the grayscale
> generated by that driver better than the djet500's anyway...
> I notice that the 'ms=' setting in your printcap file are a little
> different than mine; I'll try yours and see if that helps.

Hmm. If you can get the cdj500 driver to work on the dw, let me
know. I just assumed it woldn't as the dj500 commands page from
HP printed with a few errors. Maybe I was wrong!

> > It sounds more like you're getting a random character error once in
> > every few files.  I've seen such a thing (one page in 20 had an error),
> > but only rarely. I can't think of the error in the driver.
> 
> It seems to depends on the amount of data on the page, but for the most
> part, I get about 5-10 errors per page.  It could be though that the
> smaller files which print w/o errors just don't have the same byte
> stream(s) which generate the error(s).  I haven't tried a large ASCII
> file (greater than the DeskWriter's 8K(?) buffer) yet.

And the errors are that you just get a bit of (or a lot of!) garbage?
If it is a handshaking problem, the printer spits out the page, prints
"DTR handshaking overrun" (or some such babble), and stops, with the
status LED's blinking.

> I've tried it w/o mdmbuf as well, but with the same results.  The
> DeskWriter manual says that it uses DTR for input flow control, so
> whatever setting causes netbsd to monitor the line to which the
> DeskWriter's DTR is connected is the one I'd want to use.

Yes. But what the DW manual does NOT say is that the standard printer
cable maps CTS to DTR both ways. So for us to shut up, the DW drops
DTR (the only control output in a standard 8-pin serial port), which
we see on CTS.

Just normal old "crtscts" will do this handshaking.

Take care,

Bill