HP DraftMaster I

From: Richard Erlacher <edick_at_idcomm.com>
Date: Wed Sep 1 10:00:08 1999

My plotter, admittedly not exactly identical, but VERY similar, requires
that you load the paper, press the button that says "chart hold" or some
such, then, after allowing the plotter to look for the edges of the paper
(an important step because it initializes the origin to the center of the
paper), press "on-line" at which time the DTR light becomes really
important. Now, the plotter will work from a null-modem arrangement if you
use X-on/x-off but I've had my best luck with the cable hooked up
differently. I'd go into detail, but that was with the old v3.22 OrCad
drafting utility and it had to have a specially wired cable to work
correctly.

I've also opened the box and socketed and replaced the components on the
little serial interface board, which uses a Z-80 Dart and some 1488 and 1489
drivers and receivers. If this little comm interface module isn't happy,
the whole plotter knows about it and doesn't work well.

Back in the late '80's, when I got mine, the HP support for these (they were
still selling them) was terrible. No one really knew what was necessary to
make them work. Nowadays, there's nobody there who'll even talk about them.

If you want to test the thing thoroughly, you'll have to get some of the
toilet paper that fits it, (mine only uses cut forms) making sure you still
have the cutoff blade located in the little groove at the front and then
load the paper in the paper path (straighforward, assume the obvious) and
then send it various drawings which use different size paper in different
orientation. These machines will feed the appropriate amount, but don't
mind wasting paper, i.e. they feed the 36"-wide paper 14-15" for a portrait
'A'-size form, wasting most of the paper. That was the reason I got the
single-sheet version. I don't need it to run all night unattended, but I do
have to pay for the paper. You'll see that's not cheap. That may explain
why the drawings in most manuals are so difficult to read, having been
reduced from already-too-small drawings.

The manuals may still be available somewhere, but I would get right on
trying to find them if I were you. I made the purchase of my plotter
contingent on complete manuals, so they were included. That became a
condition after I found that Martin Marietta, after buying 20 or so of these
still hadn't received a complete set of manuals even though each plotter was
supposed to come with them.

If you have access to a Windows box with AutoCad 12 on it (I don't have a
later version to try this) you should be able to put it through its paces,
as that has an internal plotter driver which operates independently of the
one in WIndows. I've had no luck at all getting the Windows driver to do
anything. I suspect (after watching the lights on the breakout box) that
there is some incompatibility in the way they work their handshaking.
Perhaps the '488 port will work for you, if you've got one with drivers in
your system.

Dick
-----Original Message-----
From: Doug Spence <hrothgar_at_total.net>
To: Discussion re-collecting of classic computers
<classiccmp_at_u.washington.edu>
Date: Wednesday, September 01, 1999 2:43 AM
Subject: Re: HP DraftMaster I


>On 31-Aug-99, Richard Erlacher wrote:
>
>>The Draftmaster series was "current" in '88. We bought them for about
>>$10K each in '88, though I routinely see them offered nowadays at
>>$200.
>
>So I guess this is simultaneously my cheapest (free) and most expensive
>($10,000) piece of computer equipment. :)
>
>>There are drivers for Windows,
><snip>
>
>I'll have to see if there's a proper driver for AmigaOS. I don't do
>Windows (at least not yet!).
>
>>Pens from third parties are readily available and the device
>>operates as either DCE or DTE via RS232, or HPIB.
>
>I thought the thing wasn't working until I thought to try connecting it
>up via a null modem instead of a standard serial cable. My null modem
>doesn't carry the flow control lines, though, so I can overflow the
>plotter's buffer at 19,200bps. If I play with the settings I might be
>able to fix that, though. (There are quite a few menu items in there!)
>
>>Dick
>
>
>--
>Doug Spence Hrothgar's Cool Old Junk Page:
>hrothgar_at_total.net http://www.total.net/~hrothgar/museum/
>
Received on Wed Sep 01 1999 - 10:00:08 BST

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:32:35 BST