A friend of mine has recently come into possession of a relic of the 80’s – an IBM Model 7374 8-pen color plotter. Being the good buddy he is – and as incompetent with computers as anyone I’ve ever known – he decided that it would look better taking up MY floor space than it would taking up HIS. So…
Where do you go for information on something like this? IBM’s web presence would lead one to believe that they never even thought about making such a thing. I’ve found a few references that claim that this dinosaur will emulate an HP 7580A plotter, but the HP driver bundled with WinMe doesn’t seem to work. The only other references I can find to drivers for it indicate that OS/2 supported it, but that’s a dead end too. (I’m not going to set up a new system to run OS/2 just to see if my buddy’s $4 plotter works. Yeah, he got it for four bucks at an auction.)
Any ideas where to look for drivers, documentation, ANY information?
You may have a white elephant as I found with an HP pen plotter I bought surplus. I could never find a windows driver for HPGL-1 which doesn’t support primitives. You may have luck with a high end program like autocad which has its own printer drivers but I don’t think you’ll find a universal driver.
I found out that plotter is emulated by the HP 7580 (or vice versa). Haven’t found a driver for either one, but at least you now have a second avenue of search.
No, it’s not an IBM, and you musta missed the $70 S&H fee!!!
Thanks just the same!
Maybe I wasn’t clear enough… I already have this gigantic plotter sitting right here next to me. I’m hoping to be able to find information about it – drivers, manual, DIP switch settings, etc. – that will convert it from a well-made electric doorstop into a machine that produces drawings.
Yeah, as I mentioned in my OP, I caught the HP 7580-emulation thing. I’m running Win Me, which has a bundled driver for the HP 7580A, but it doesn’t seem to do much.
This thing is one cool piece of hardware! Lotsa lights and buttons, even a joystick on the front panel that lets you make your own drawings. It would be slick to teach this Neanderthal to speak English, ya know?
Umm… your best (or at least easiest) bet is to get a null modem cable and see if you can communicate with the unit via a serial port. BTW I think the IBM 7374 may well be the HP 7580 internal hardware wise.
Try these DIP settings and see if they work with a null modem cable and 7580 emulation.
Dip switch settings for the specified printer:
At com port set 9600 baud rate use the following dip switch settings:
1 UP
2 UP
3 UP
4 DOWN
5 UP
6 DOWN
7 UP
8 DOWN
9 UP
10 UP
Switch settings on plotter:
INTERFACE MODE: RS-232-C
Dip switches:
EXPAND --X NORMAL
EMULATE --X NORMAL
STAND ALONE X-- EAVESDROP
MONITOR MODE --X NORMAL
LOCAL --X NORMAL
PARITY ON --X OFF
OFF --X ODD
DUPLEX-HALF X-- FULL
HARDWIRE X-- MODEM
DTR BYPASS X-- NORMAL
Here are some communication tips. It’s for a different series of plotters but the idea is the same.
astro, my hero! However, this IBM monstrosity doesn’t want to talk nice to me – or to you!
There are only four DIP switches on the back of this one, like this:
PARITY ON – PARITY OFF
PARITY EVEN – PARITY ODD
EMULATE – NORMAL
EXPAND – NORMAL
In addition, there’s a tiny li’l black push-button labeled “Conf. Test.” And a rotary switch that selects baud rate, which is set, I think correctly, at 9600.
I was in the HP factory in San Diego, where they made their plotters, in the early 80s. There I saw large-format plotters being made with the letters “IBM” silkscreened onto them instead of “HP.” This would have been right around the time the 7580 was a current model.
Yes, the null modem bit was the trick I had missed. BTW, a null modem adapter from Radio Shack worked with the straight serial cable I was trying to use.
So far, I’ve been able to print out the standard Windows printer test page successfully. Now to try and make the thing work well enough to produce a drawing of some sort!
As previously stated, using the bundled driver for the HP 7580A, the plotter successfully printed the test page.
I downloaded Design Workshop Lite, a pretty nice CAD program, and drew something simple – essentially straight lines at various angles – in two dimensions. The plotter reproduced it precisely.
I created another 2D drawing using some curves and such, and the plotter reproduced it, sorta. It drew part of it great, but then, like, forgot what it was doing and dragged a straight line right off the page. This happened several times.
I downloaded an actual architectural 3D rendering of a fairly standard house, called up a 2D plan view, and tried to print that, but the results just get weirder. The first shot, it drew part of it in recognizable form. Later attempts were completely unsuccessful, with the plotter drawing straight lines at odd angles radiating from a central point, banging away for 10 or 15 minutes until the pen had torn a hole in the paper at the central point.
I’m wondering if it’s a compatibility/software issue. I’m also wondering if it’s a cabling issue. I’m also wondering if this IBM 7374 is truly an HP 7580A at heart.
And I’d give my left nut (maybe) for a user’s manual for this antique.
Is there any indication on the plotter where it came from? That could be a place to start. Check with your local IBM office (if you have one). You might luck up and find an “old timer” who could scrounge around and find a manual.
Try adjusting your windows serial port settings. Set the FIFO settings to 1 byte. This might be causing a problem since when the printer signals that it’s buffer is full there’s still 15 bytes left in the output buffer that are going to go to the plotter. The thing is old, they probably didn’t have FIFO buffers to plan for back then and it might send XOFF when there’s only four bytes of buffer left, to make best use of the small buffer it likely has. (RAM was expensive back then.)
Also make sure everything is set up to use the same kind of flow control. Nothing worse that using hardware flow control on a plotter that only does XON-XOFF.
