In 1984/7 I played the Jungle Lord quite often in the local pub. Then I was able to lay my hands on a playfield. The idea was to use an obselete XT- or AT-clone as in- and output for this field. But some weeks later I could buy a complete machine and the project was discarded. FYI: this machine is equiped with a 6802.

But even after 20 years I'm still thinking about this project; not only as "just for the fun" but to have a spare computer at hand. Beside the original idea using a PC-motherboard, I'm also thinking about using a Commodore 64 as base.

I'm quite sure your program is meant for a complete different pinball machine so I imagine I cannot do much with your sources. But could you tell us please about the philosophy behind it and your experiences? For example, what I would like to know is how you scan the playfield; interrupt driven, like the C64 scans it own keyboard, or in a continous loop, like the KIM does?

Thanks for any info!

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Ruud, my apologies for missing this post for 8 months. Had not been reading in here and all.

My code is for an upcoming replacement board for the Bally Brain series. They made a series of home pinballs, their most famous being Fireball.

http://www.ipdb.org/showpic.pl?id=4116&picno=16561
http://mirror1.ipdb.org/images/4116/image-10.jpg

The CPU uses the Fairchild CPU. And that is the killer. If the chips go out, literally no one can repair them.

My design is based on Daryl's first SBC, but with some twists I needed. It is not compatible with his design. A POST LED for example.

The hardware requires a constant strobing of the matrix lines. It uses the same 8 matrix lines to run the dispaly, switch and light matrix. Less wiring but curiously strange. So one requirement, the matrix has to be kept going. The original design changed the matrix strobing speed to change the music pitch.

I run it at either 30 or 60 hz, I forget which right now. For some reason, I have lousy luck with interrupts so I am not using them, though the POST routine does test the interrupt from the 65C22. The basic loop is simple.

POST
init variables

LOOP
jsr hardware processing
jsr software processing
jmp LOOP


All forms of inputs and flags are read on the fly as the loop is constantly running. I use a small delay routine at the end of the software processing.

One thing nice about the 65xx series is the immediate memory access which the AVR is pretty painful about. Since I set up with 32k of ram (-256 bytes for i/o), I use software variables like they are going out of style. I expect to have about 2,000 variables when all is said and done.

This shindig has been going on about 4 years now, back into it once again. (still tweaking the score display message routine to be real easy to use.

If you want, hit me up with a private message and email and I can send you the code if you want. It has a ton of comments.

Again, apologies for not answering for so long. (lousy job I got out of, got busy, new job which is much better right now

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"My biggest dream in life? Building black plywood Habitrails"