Your board looks fantastic with a really clean layout. Definitely nice to have this option available and will try to build one up. I’ve fixed quite a few Gameplan boards. When the corrosion is mild those are still worth saving but others that are too far gone I’d rather build up a new board and move over some of the components. I still have an original MPU that is stripped down but it needs so many traces fixed it was just not worth all the work it would need.

If you want someone to do a test build I'll be glad to buy one of the blank PCB's and already should have all the parts on hand to populate it. I have two Sharpshooter games side by side. Have them both running now and helps to have them set the same as I was using one as a test jig for repairs.

Robert

That's awesome! Looking forward to doing a test build.

As soon as the latest updates are applied for a revised board (additional vias for power) then can see about making up a few boards. I don't mind building some or putting some kits together.

Robert

I used a different board house. A small batch just came today. Going to work on a test build and docs. I have most of the parts but I need to order a handful. Hope to work on it over the long weekend.

Robert

I’m working on assembly docs and doing a proof build. Will have individual boards available and working on a kit. There are some parts I don’t have but could at least get a partial kit where you wouldn’t have a lot of parts to chase down.

Actually I think the issues that were flagged had to do with the vias. On the boards I got the vias are still covered. I think they would have to be larger with more of an exposed larger ring in order to allow them to be uncovered. If there is another revision perhaps that can be done and make the via hole sizes large enough so at least a small wire wrap wire can go through them.

This batch should still work as they are and now with all the extra vias added to the thicker power traces that addressed the main concern with the initial prototype board.

Gathering and sorting kits takes time! I'm putting together about 6 kits and going to assemble a few boards. There are some parts I need to order. At the moment for the kits it looks like I will be able to provide almost full kits. Just short on some of the IC's. Will see how people like them and perhaps I can try to a batch of full kits. Working on the draft for the assembly docs and am doing a proof build this weekend.

Under the ROM folder which one of the .BIN files is the recommended one to use?

Made progress on a test build and progress on assembly docs. I think the docs will help anyone building one of these boards as a kit. I'm missing a few parts and will get those ordered soon. Should have a few assembled boards and about 6 kits. Started packing the kits and most as labeled to make it easier to sort the parts. I sent a very early draft of the assembly docs to Jeremy and am working on adding the rest of the steps.

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It helps to have a variety of lead forming tools to get nice bends on the parts. The spacing on the small diodes was smaller than most of the ones I use but I found some additional lead forming STL files on Thingiverse and one of those worked perfectly.

Just received a few more parts. By next week I should have the rest in to have some full kits ready.

I did have enough parts on hand to finish one of the new MPU boards. Booted right up and seems to work perfect in SharpShooter.

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The updates look great. Let me know how the docs go and I'll make any needed updates. It is an easy board to assemble but those not used to soldering will just want to pay extra attention to the close lead spacing on the Q1 transistor. It's fine but easy to cause a bridge if not careful. Some solder wick can be used it anyone gets a bit too much solder there.

I built a couple more of these Multu MPU boards and ran them in SharpShooter. These were made with all the parts that came in so I could confirm the parts were all ok. I'm just doing a couple quick revisions to the assembly documentation but it is setup so you can easily follow it step by step. It is an enjoyable kit to build and you should be able to get it together over an evening or two.

I have a couple fully assembled/tested boards available and a few FULL kits that include everything needed. The PCB and all parts including NVRAM, EPROM, CPU, etc. and a printed copy of the instructions.

I'm building one additional board for testing and am going to install a battery holder for a coin cell to see how that works. Will let everyone know.

Jeremy definitely did a great job on the board. It is laid out very well and the ones I built all worked the first time.

Hello Doug, I just e-mailed you the latest version V1.2 of the assembly doc.

The first couple of FULL kits were mailed out and should be delivered on Saturday. Will be interested in hearing feedback.

Still have a few kits left. If there is interest I may do another batch of kits after that.

I just built a board using a coin cell and a low power 6264 SRAM chip instead of NVRAM. if anyone goes this route I have a suggestion.

Install a 1n5817 in D60 where the 1N4148 was supposed to go. With this change I was able to pick up an extra .3V at the RAM chip. Then I the 1n4148 or a 1N4006 in D59 where the 1n5817 originally was.

Going to test this board at lunch.

I have one already assembled that isn't claimed. It is available.

Robert

Do you like to solder? Still have a kit ready to go but I could assemble one. May be next week though.

That is awesome news. Can I add that to the next revision of the docs? Also can add a note at the end on who the thank for that!

Some more good news. So far the new MPU board seems to run well using a low power 6262LP (or 6264ALP) chip with the coin cell. I am using the mod of swapping the two diodes I mentioned earlier in the thread. Left it in the game to continue running and additional testing but it seems like a good option.

Will update that in the docs too.

Still have a couple kits available. After that will wait to hear feedback and if there is interest could probably do another batch.

Robert

Sure, just send me a pm with your e-mail address and I can send it later today.

Robert

The last couple original GamePlan boards were total time sinks dealing with bad traces, etc and rebuilding traces, etc. Now I will only fix clean boards or ones with very minor battery damage. Otherwise I'll just build a replacement.

I use the CR2032 size which is really common. I’ll see if I can find a part number or link for the holder but it seems to be a common size too.

Jameco should have the 6264LP chips but it looks like their site is offline at the moment.

Looks like you can get the 6264LP from Great Plains Electronics

https://www.greatplainselectronics.com/proddetail.asp?prod=6264LP-55

This is the style battery holder that I used:

https://www.amazon.com/RuiLing-CR2032-Button-Battery-Holder/dp/B07PNK5D6H

Make sure to put the 1N5817 in D60 instead of the 1N4148. In D59 you can probably use the 1N4148 but I put in a 1N4006.

So far that is working great and running in my 2nd SharpShooter now.

For a whole new board or future new boards it would be good to ensure orientation is the same. But the board works great as it is and Jeremy does have it well marked. Since it is a larger 40-pin off by itself it really isn’t a big concern. If it was one of the smaller IC’s backwards mixed in then it would have been flagged early on.

I can add a special note in the next version of the build docs to call attention to the orientation of that 8255 chip and it should be good.

Except that anyone used to working on GamePlan boards would be used to it oriented as it is. Matches the orientation on the original board. The board is well marked and no issues building.

Possibly. But I’ve seen boards come where people did that even if they were all in the same direction.

Adding an extra legend is fine but since there are already boards out there at this point I wouldn’t want to see the chip orientation change. That would be really confusing to have some nearly identical boards with different orientation of parts.

If extra marking on the board is done or not, since the issue was raised it will be clearly noted in the docs. I’m going to mention to double check that the notches in the sockets match the board layout. If I ever come across boards where a socket was backwards I will fix that. Back in the 80’s Heathkit had a bad habit of doing that on many factory assembled boards. Use that as an opportunity to install better sockets.

I’d consider it more of a discussion and it was a good point to bring up. Don’t get discouraged and you have a lot of knowledge to contribute. I try to keep orientation the same on my own boards when possible as it is a good practice. However at this point to change that one chip on this particular board may cause more issues if there are two similar boards with just one chipped reversed. Potentially someone could have both versions on the bench and that would mess people up.

I’m sure there can be some additional updates to the silkscreen to take care of this one.

That TL866II programmer should be able to do the 27C020 EPROM ok. It has trouble with older EPROM chips and would never trust it to do earlier EPROM's that need 21V or 25V. I've read about hacks to make those work but would just use an older programmer for earlier chips.

Just reading/verifying chips seems to work well on all.

One feature that was a really nice surprise on that TL866II is the logic and chip test function. It seems to have issues testing some open collector IC's but it does a very good job on the others. Many testers just say a chip is good or bad. The test in the TL866II also shows which output pins are at fault. Nice to see if teh whole chip is dead or just one or two outputs. Great for confirming the chip was really a problem.

The other perk is that the TL866II also tests the 8255 chip which is the only stand alone tester I've seen for those. Helped me weed out a couple bad ones on original GamePlan boards. Totally worth the cost as an extra piece of test gear.

As I recall that MOD-MEP had different versions of the software for it. Earlier version maxed out at 27C010 chips but I know there was a later version that could do 27C020 chips. However that software may not be easy to find anymore. Used to be on the JDR microdevices FTP server but I have a feeling that is LONG gone.... Maybe it is archived somewhere.

May want to look on FB marketplace or CL since you could probably get a PS/2 keyboard for almost free these days. I've given some of my spares to neighbors.

Did a quick search and it looks like the latest MOD-MEP programmer software was saved in an archive. I think the 912 version is the latest. Found it here:

http://www.bitsavers.org/test_equipment/modularCircuitTechnology/jdr/

Later versions should work. You may want to revive that old machine. That programmer can program chips that the new programmers can't....

Glad that things are going well so far. Planning on another update to the assembly docs and can add a note for those two resistors if they were tough to find. The more parts you get on the board the easier it gets to find the rest.

For building boards I use my trusty Weller WTCPT unit. Tried some of the lead free solder years ago but am not a fan of it. Prefer classic lead solder either 63/37 or 60/40 then clean the boards and dry after soldering.

I did another update to the assembly docs and sent the latest to Jeremy. Now that it is cleaned up I thought it should be posted with the rest of the design files for the board.

I need to make some additional EPROM's soon. If anyone needs one to complete a build let me know as I can make extras.

I’ve built several of these boards and so far they all worked without issues. I’ll take a look at the other boards to double check that area. If there is too much heat it is possible to lift a pad on any board. I can add a note about that if I have to make any other revisions to the docs.

The more you solder the better you get and I look at kits as a way for people to learn plus get the enjoyment of building. Also ultimately the satisfaction that they did it themselves and it is the board they built running in their own machines. There is a lot to it and you basically built your own new computer board and it works. Glad that it all worked out and you have a running machine again.

For building these boards if you want really nice looking components it helps to have a lead forming tool or set of them.

For the small diodes and resistors I use one like this:

https://www.amazon.com/CANADUINO-Bending-Resistor-Forming-300-700/dp/B089NZVB7S

These are also handy to have:

https://www.amazon.com/KDHLJ-Benders-Resistor-Capacitor-forming/dp/B07L4PVWWG

If you have access to a 3D printer there are ones you can download and print.

They save time preparing the components and they look a bit more uniform once installed.

You can see the latest version of the assembly docs for the new board here:

https://github.com/jfleitz/gp-mpu/blob/main/docs/GP_Multi_Assembly_V1.3.pdf

How is everyone doing on their builds? So far the feedback has been good. Any held needed? So far most issues have been with the machine itself.

This one?

https://pinside.com/pinball/forum/topic/game-plan-owners-club-sharpshooters-welcome/page/15#post-6950995

<blockquote

The assembly docs have the list of parts needed. If you are sourcing parts you will probably need to hit at least three or more sources. For the PCB you’ll have to get some fabricated or get those from someone else who already had extras made. You’ll also need to program the EPROM.

There are a couple different ways to build the board. If you use an NVRAM chip then the battery section isn’t populated except for a jumper instead of a diode. If you use an 8K low power 6264 then the diodes are populated (swapped locations on board) and either a coin cell holder or three pin header for an external battery pack. I’ve built both versions and they work great.

To save people time I put together a limited number of full kits with everything needed. All parts ready to go. Just need to add solder.

Robert

For anyone that wants a full kit with everything included you should jump on this. I am out of kits. Since I am set on boards for myself and have a bunch of other projects I need to work on I'm not sure when there would be any more.....

There is an update coming to fix an issue with the display connector for the Cocktail machines. The board works flawless in all the standard upright machines but it needs a few traces fixed for the connector used by the cocktail games. Testing the fix for that and I plan on adding notes to the assembly docs about updating the older boards so they will run in the cocktail games.

Jeremy did a fantastic job on the design of these boards and they work really well. I know of one arcade that has one running in a Sharpshooter every day all day without issue.

I wrote up some assembly documentation as my contribution to the project. I also made a couple batches of complete kits for people. If there is enough interest I may make up one more batch on an updated PCB with the fix for the cocktail games.

V1.4 is the version of the board I am working on. I think I have the updates done to the board. Just haven’t confirmed it yet. In order to test I had to get a couple cocktail displays (unknown if working) and had to make a cable. The cable is odd with pins removed from each of the display connectors. Lots of variables but once confirmed will post a method for updating it.

I have good news! Just confirmed the updates to the rev 1.4 board. 4 cuts near the J5 connector and 5 jumpers.

The ribbon cable not only has a couple pins out on each of the connectors they also have a twist in the cable. All good and now I have a full set of Gameplan displays for bench testing any of the boards.

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If you use the V1.4 or earlier board in a standard upright pinball machine then this modification isn't required. It is only needed to fix an issue with the display on cocktail games using the J3 connector.

I am going to try and add the following set of pictures to the assembly manual but in the mean I wanted to post the fix for cocktail display J3 connector on the V1.4 boards (may work on v1.3 but don't have an example here to try).

There are two issues. One was a missed ENABLE signal going to the J3 for the cocktail displays. The other was something that was sort of caused by the way Gameplan renamed signals for the same lines. On the cocktail connector the display clock lines were renamed. They actually trace back to different lined on the J9 connector for the upright pinballs. The renaming of the signal lines can frustrate someone doing repairs too.

In order to fix this (4) four traces need to be cut and then (5) jumper wires added. This is best done with a fine wire wrap style wire. The pictures in this first post show an image of the board along with an image showing the three cuts on the top and one cut on the bottom. I use a sharp hobby knife and use a meter to confirm they are properly open. So, 4 cuts and 5 jumper wires and then the cocktail displays will work on that J3 connector.

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First three jumpers installed on the component side of the PCB.

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Pictures that show the long two jumper wires that need to be added. After these are complete you are ready to use the board in your cocktail games.

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I believe the J3 connector has been fixed in the latest PCB files so this fix should only be needed on V1.4 and earlier PCB's.

Anyone soldering your own boards may want to reference this excellent guide by NASA:

https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/601%20General%20Requirements.html

First I would try some of the other game selections. If you turn off all 4 switches and set it for Sharpshooter will it boot and stay up? To me it sounds lie it it booting but at some point crashes, watchdog kicks in, and it reboots. I would triple check all the proper components are installed in the proper locations. Maybe try a different NVRAM module.

I still have some of the spare components and thinking about making up some additional full kits like before. Anyone looking for a kit or fully assembled board? These will have sockets for all the IC's.

Just want to confirm the latest PCB files and will probably get a batch of boards made.

I have some PCB's on the way. I'll do a proof build just to confirm everything is good and will get some additional kits packed up.

I did a couple proof builds which went well and shipped out one of the assembled boards. I have another assembled/tested ready to go and the kits are all ready as well. If anyone would like one just send a PM.

Do you have a logic probe? Can you check the reset signal on the CPU to see if it is resetting? Can you verify the EPROM is properly programmed? Do you have any IC chip testers? Some EPROM programmers like the TL866 can test many IC chips including the 8255 to confirm they are ok. However it doesn’t seem to do well at testing open collector IC chips and can flag good ones as bad.

Do you have an EPROM programmer? If so did you program the EPROM chip? If that isn't programmed with the code on it then the board won't work as there is no code for it to run.

What programmer do you have? Reason I ask is that some of the programmers have a logic test feature and also act as a chip tester.

What binary file did you use?

Can you triple check on the back of the board for any solder bridges? Some of the pads are close together and can accidentally get a solder bridge.

Not sure where you sourced all your parts from. Did some come from China directly? These days there are lots of fake an remarked IC's out there.

Have you checked to ensure all the IC leads are actually in the socket ok. I've seen cases where alead folds under the chip instead of making a good contact and going in the socket as it should.

For all the boards I've done and kits I prepped I made sure to test the IC's. ACtually had a tube of NOS 8255 chips from NS and found a couple bad ones. Can't always assume the chips you got are ok.

One like that can do a decent job on testing many of the 74 series logic chips and the lm339.

Another thing to check is the revision of the PCB and how you configured power for the NVRAM. Newer versions have a couple pads that should be jumpered. If using a STATIC RAM you can use a battery but install diodes. Need to double check that too.

Those look correct. Also looks like you have real CPU and CTC chips.

When things don’t work can’t make any assumptions so that is why all the questions.

Have you gone through each of the settings (by using the test button on the coin door) then pressing the button on the MPU to reset each one? If not there will be garbage data in the NVRAM.

Have you replaced any of the capacitors on the Power board?