Slither question - P1 & P2 "jump plugs"

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Slither question - P1 & P2 "jump plugs"

I'm going to try to hand-wire my own Slither DSR board to try to convert a Qix set, most of it looks pretty straight forward but on the schematics are two "jump plugs" for selecting the type of EPROMs from 2716 and 2732. I'm not an electronics genius by any means so I was wondering if these are as they sound and are simply just straight through jumpers? If so can anyone tell me what their configuration is as the schematics don't show which pin jumps to which? I find it a little hard to believe that this board, the only part keeping a Qix set from being a Slither, is simply made of off-the-shelf parts with no design protection against what I'm trying to do, but thus far everything I've seen seems to indicate that.
 
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The purpose of the jumpers is to select between the use of 2716 or 2732 EPROM's on the DSR and video boards, respectively.

26-00002-016 jump plug is used if 2716 EPROM's are used and 26-00002-032 jump plug is used if 2732 EPROM's are used. How they are internally wired to do this I do not know, but would have thought someone knowledgeable could tell from the schematic.
 
The purpose of the jumpers is to select between the use of 2716 or 2732 EPROM's on the DSR and video boards, respectively.

26-00002-016 jump plug is used if 2716 EPROM's are used and 26-00002-032 jump plug is used if 2732 EPROM's are used. How they are internally wired to do this I do not know, but would have thought someone knowledgeable could tell from the schematic.

I can probably bumble my way through the problem eventually, I was just hoping someone might have some ready insights into it.
 
Okay, after taking an ohmmeter to the plug:

If you number the pins like this:

jump_plug_26-00002-016.jpg


the connections are as follows:

1-8
2-9
3-10
4-11
5-12
6, 7, 13, and 14 are dead. They don't connect to any other pin.

Whatever sense that makes.
 
The above pins are numbered incorrectly, pin 1 is at the bottom left of the chip (indicated by the dot) and you count anti-clockwise from there.
 
The above pins are numbered incorrectly, pin 1 is at the bottom left of the chip (indicated by the dot) and you count anti-clockwise from there.
Thanks for the information. However, how one identifies the pins is actually irrelevant to the information being provided.

The connections I found by testing are accurately reflected, given the designations labeled in the picture. (Which, as Hewitson points out, may well not be the standard.)
 
Okay, after taking an ohmmeter to the plug:

If you number the pins like this:

jump_plug_26-00002-016.jpg


the connections are as follows:

1-8
2-9
3-10
4-11
5-12
6, 7, 13, and 14 are dead. They don't connect to any other pin.

Whatever sense that makes.

Man you're awesome! Those pictures you took for me too are invaluable, I'm taking the schematics from the manual, cleaning them up and using the pics to compare anything that's tough to read. Here's some of the work I've done so far with the video EPROMs, there's still a lot I'm going to have to trace or figure out. BTW given what you've shown with the JP1 connections I'm surprised they just didn't use a dipswitch, which is what I'll probably put, why make a weird custom part?
 

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I'm not sure if this will help, but I've got a slither CPU pcb in my zookeeper. No modification was needed except I've got a dual frequency wells gardener k7203 (has switch on frame). I had to flip the switch to get the game to sync correctly.

Just thought this might help ya.
 
I'm not sure if this will help, but I've got a slither CPU pcb in my zookeeper. No modification was needed except I've got a dual frequency wells gardener k7203 (has switch on frame). I had to flip the switch to get the game to sync correctly.

Just thought this might help ya.

Thanks that's very helpful actually as it helps confirm what I suspected, which is that all that's really needed to convert a common Qix boardset to Slither is that DSR/CPU board, otherwise this would probably be a little too much for a first repro project. Which is why I'm trying this to begin with, not only is Slither just a cool game that's fairly rare and expensive to get but seems to be a sitting duck for reproduction as it's apparently not too complicated, looks like it's all off-the-shelf chips and the ROMs are easily obtainable. I've got a few other fastasy PCB repro projects in mind but figure if I can't even handle this one I've got no business thinking about that others.

My plan of action stands as this:
- Get a Qix boardset and confirm it works (on order)
- Wire up a hand made Slither DSR and confirm that it works, that I understand the circuit and it doesn't hold any nasty surprises
- Figure out how to reduce the component count, I can already see a lot of identicle resistors in the controller interface circuit that could be substituted with a few SIPs. Also see if any improvements can be made like say a better amp, trackball compatibility changes if needed, using less but bigger EPROMs, removing the need for a battery, etc.
- Design a new foil pattern with these changes, have one made, confirm all is well, see how much a small run would cost and check interest.
- Live happily ever after until the next project.
 
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Sounds like a great concept.

That said, it is my understanding that working Qix and Zookeeper boardsets are not easy to come by either.

The other games that run on the same hardware are even more rare.

Get this working and then build up replacement parts for the REST of the set too! You GO boy!!
 
Sounds like a great concept.

That said, it is my understanding that working Qix and Zookeeper boardsets are not easy to come by either.

The other games that run on the same hardware are even more rare.

Get this working and then build up replacement parts for the REST of the set too! You GO boy!!

Zookeeper boards? Errrr... perhaps not so common, and people tend to hang onto those, especially if they're working. But I see Qix sets turn up all the time, in fact there's a couple set on Ebay right now, and while a lot of them don't work if one is willing to fix them they're a LOT more common than Slither sets. In fact the last full Slither game I saw went for over $1000 on Ebay, but that was probably a bit excessive though, I've heard that they're typically worth about $600 to $700 working and in reasonable shape. I understand that it might be able to get converted to Space Dungeon too and I may take a crack at that one at some point, but I'm primarily interested in Slither right now.

And as far as doing to main board too goes that thought has crossed my mind, it would certainly be handy for people fixing games that use it and there are a few, but I've got to see if I can tackle this before going on to bigger things.
 
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