HP-85 running a special version of Asteroids (game) that uses the HP 9111A digitizing tablet for input.
HP-85 running a special version of Asteroids (game) that uses the HP 9111A digitizing tablet for input.
I have two of these digitizers, both in working order the last time I used them. The really weak aspect of the design is that the cord for the pen is directly attached to the unit, so the cable may be damaged near the point where it enters the main unit. You may need to reinforce this part of the cable to avoid further damage. Also, when buying a used HP-9111A be sure that the pen comes with the unit and that the cable is intact (unfortunately in some cases the cable has been cut and the pen lost, rendering the unit unusable).
I did not intend to purchase the second one in my collection, but saw it on eBay for a very low price and decided to go for it. Consequently, my bid was very low and someone else won the auction. Thinking that the winner would probably be a fellow collector I looked at his/her(?) ebay history and what I saw did not fit the profile. So I sent a message to the winner explaining what the HP9111A is and that it would be unlikely to work with a typical Windows PC. Sure enough I got an answer to the effect that the purchase was a mistake and whether I wanted the device. I think we actually arranged for the seller to sent it to me directly to avoid additional shipping costs.
Although HP no longer sells the 09111-68701 Stylus Refills package, the refill is commonly used in ball-point pens. It is very important, however, to note that the refill body must be metal, not plastic. The reason is that the sensor inside the stylus is shielded by the metal stylus enclosure, and relies on the refill housing to act as an antenna. If you use a plastic refill, the sensor will not get anything from the tablet, causing you to think that the tablet is malfunctioning.
Note also that you may need to salvage the plastic O-ring from the original refill, because this is needed to hold the spring in place.
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The 9111A Operator Manual. How to plug it in, run the diagnostics, etc. |
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The Programming Guide to the HP 9111A. Very interesting manual, tells you what you need to know to write programs that access the HP 9111A. More a tutorial than a reference guide, keep notes while you read it, otherwise, if you miss something, you will not be able to find it easily again. Best read with an HP-GL manual near by. |
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The System Tools manual describes
a set of programs that allow the HP-86/87 to be used as a CAD system.
Don't expect
anything worth writing home about, the HP-86/87 is so slow as to make the whole
thing a joke, but it is impressive that HP could make the HP-86/87 do
all this stuff, despite its minute memory and slow processor.
The programs described in this manual are available in the Drawing Tools Disks for the HP-86/87. |
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9111A Graphics Input Tablet, Keyboard magazine, Nov-Dec 1980, page 9. |
| Utilities Disk for the HP-83/85 | Documentation: no supporting documentation |
| Drawing Tools Disks for the HP-86/87 | Documentation: System Tools Manual |
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The HP 7470 Interfacing and Programming Manual includes a detailed description of the HP-GL commands and principles of operation. |
Many thanks to Mr. Glenn Sherwood for scanning and sending me this material.