i see a 6802 cpu, crystal a 6116 ram and no 6810. so the clock gen is different than original (same approach I did).

Kinda off topic but no dip 26 and 27? He has machine pin socket female strip there and marked as not used?? is dip switch 26 and 27 really not used in any game?

everything else looks the same, so treat it like a bally MPU.

Start here

CPU P40 = high
CPU P37 = pulse at 0.5mhz

I see a burnt looking 82 ohm resistor in the reset area. Check him for open. That ram would get no voltage if he burns open.

Getting a little off topic here... but using a 6800 CPU would make no sense to me.

First of foremost the 6800 is rare compared to the 6802. They made the 6802 in way higher quantities, probably 100x more 6802 was produced than 6800. That makes it cheaper and easier to get.

The 6802 has internal ram in the right place to eliminate the 6810 at U7. Pointless to re route the U7 ram into the NVRAM. Just open up the NVRAM so homebrew software guys can use the entire thing. Saves a dip24 socket and ram or extra circuitry to reroute enabling to the nvram.

6802 also has internal clock stuff. Sticking a crystal across p38 and 37 is so simple. You can use a complete oscillator if you find getting a 2mhz crystal to start up fast enough is a problem. Using an external inverter and clock circuit is just more parts to stuff.

Back to the NVRAM... when using a FM16W08 you don't need the diode blocked VUA-Q2 pulling up the d3-d7 since there is no battery backed ram. Sip resistor pull up all eight data bits. That means you don't need a stiff 150 ohm pullup resistor either. When not pulling d3-d7 vua-q2 and you are not buffering a clock gen you can easy a cheap common gate here like 74HCT00. When you go down to just one ROM you might even find an extra gate elsewhere to completely eliminate the need for u15. That move saves at least nine parts.

Also the NVRAM can be put right on the main vcc rail. It does not need to get powered off of the reset delay. FM16W08 plays nice in this system. Saves that dumb 82 ohm resistor circuit dropping the 12v down for the ram thats wastes power.

MCP130-460 reset monitor simplifies things even more saves another 10 parts or so.

Hrmm

Sounds like it does not reset on the bench until you mess with the 12v rail (probably normal). Try triggering a manual reset by forcing CPU p40 low (bridge cpu p39 and p40 together briefly) and then count the flashes again. Watch this if you need help understanding the flashes.

Note the pause between flash ROM test and RAM test (normal). Also you can't notice the flicker on this MPU (to fast for the LED / Camera).

If your consistently getting six flashes on the bench, you are in good shape. You won't see the 7th flash without the 43v going to the MPU.

same as the original manual. so check the EBD manual.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Your RAM chip has a battery inside of it and looks to be 19 years old now. If it dies the audits can scramble and you may get corrupt value in the current credit audit. Audit 5 is the current credit audit. Use the test mode to get to audit five and push the "activity switch" as it is labeled on your mpu top right of the MPU to clear that audit back to zero. Then see if you can add credits and start a game.

The test button inside the coin door grounds MPU J3 P1. The diag button ground return goes back to driver J2 P7. I would track out those two connections first so you can get into test mode.

You can also manually ground MPU J3 P1 to get into switch test and see what is registering or not. The start button switch also goes back to J3. Make sure that connector is on correctly. Your picture shows something odd at MPU J3 (bot right). It looks like the connector was split into two which would make it easy to get mixed up.
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One side of the test button goes to J3 P1. The other side of the test button goes to ground on the driver board. Pushing the button then grounds J3 P1 which should make it go into test/audit mode. The test button does not go to MPU J2. But keep in mind strobe 1, return 1, and etc at J2 and J3 are the same thing. J2 goes to the playfield. J3 goes to the coin door/cabinet.

Since you cannot get into test mode, start the game or coin up i'd start on figuring out J3. Seems likely the connector hack is causing a problem.

If you use a gator clip with one side on ground test point or ground braid, then carefully touch the MPU J3 P1 connector pin and it should go into test mode. Four times to step to switch test mode. Then you can put the plug back on and check you switches.

Yes that is booting up fine.

Lights on coin door is general illumination Always on lamps and not cpu controlled.

When the credit display shows 00 its in switch test. You can plug the switch connectors back in once in switch test and then see what switches registering correct or not.

Looking like mpu J3 needs repinned. Get a molex style female side instead of press in IDC.

In solenoid test the flipper relay will click but the flippers will not pull in unless you have the flipper buttons held down when the relay clicks.

if switch test shows 03 when both MPU J2 and J3 are unplugged I would think then MPU has a problem somewhere in the return 2 (I2) circuit. Your video appears to show that the start button is stuck which makes the aduit value scroll up. During this video do you have MPU J3 and MPU J2 on or off the MPU. The start button is at Stobe zero and return 5.

To look for an issue on the MPU in the return 2 area you can measure for 56K resistance across C24 (and all other return capacitors). If zero resistance or less than 56K replace C24 isnt shorted. If over 56K resistance replace R44 (56K pulldown resistor). Open all dip switch banks and try switch test again. Check diodes CR40, CR32, CR24, CR16 for being shorted or broken. If the checks above test out OK, then maybe U10 has a problem?

If the switch matrix issue is on the playfield a new replacement MPU is not going to fix. So figure out where the problem is before replacing the MPU.

Unplug the playfield switch connectors on the MPU and close switches by shorting strobes to returns right at the MPU male connector pins. Work your way through the problem switches. If you get all right numbers closing switches at the MPU the problem is on the PF. If the switch count is still wrong the problem is on the MPU.

$40 less than Alltek =D.
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The fact a connector post is melted makes me think coil voltage shorted to a switch and dumped a lot of current through a PIA port damaging it to the point it melted the connector. J3 typically goes to the coin door, so look around there. Like a coin lock out coil is not shorted to a coin switch or something like that.

Checking switches at connector pins remove both of the switch connectors on right side of MPU. Then short from ST0 to I0,
then ST0 to I1,
then ST0 to I2
....
ST0 to I7
ST1 to I0.

You should get a unique number in switch test for each connection. If wrong numbers come up the MPU has a problem. Since ST1 connector is melted I'd guess U10 is damaged

Not figuring out why the switch connector burned on the last one before hooking up a new MPU puts the new board at major risk for same problem happening to the new MPU.

The same PIA port that handles switch matrix also controls the display. So a switch problem can manifest with the displays. Sounds like you still got a shorted switch. If the display problem goes away with the switch connectors off its for sure in the switch matrix wiring.