Arcade Fix Popeye Board Repair Part 10 Popeye Died Breakout the Logic Probe

SAM'S ARCADE FIX- POPEYE BOARD REPAIR PART 10 - POPEYE DIED, DID HE FORGET TO EAT HIS SPINACH?
LET'S BREAKOUT THE LOGIC PROBE
In this video I revisit my Popeye board that I bought on Ebay and repaired about 2 and a half years ago. Some would say it was a basket case, but I got the game working. About a year ago I started to install it in my Donkey Kong Jr cocktail and the board had died sitting on the shelf. That board has been bugging the - you know what out of me, so I decided to get it back out and break out the logic probe. Can I fix it again? Let's find out.

[@waynegram8907]

What does the Bus Request signal do to the game board? I'm not sure if all arcade games have a bus request signal

[@SamsArcadeFix]

Here's what the Z-80 manual says. BUSREQ. Bus Request (input, active Low). Bus Request contains a higher priority than
NMI and is always recognized at the end of the current machine cycle. BUSREQ forces
the CPU address bus, data bus, and control signals MREQ, IORQ, RD, and WR to enter a
high-impedance state so that other devices can control these lines. BUSREQ is normally
wired OR and requires an external pull-up for these applications. Extended BUSREQ periods
due to extensive DMA operations can prevent the CPU from properly refreshing
dynamic RAM.

[@waynegram8907]

@@SamsArcadeFix That is Correct but PopEye doesn't use DMA or Dynamic RAM so I'm confused why Popeye is using the BUSREQ signals to do what? Most arcade games that use a BUSREQ signal has DMA or Dynamic RAM or PIA chips but Popeye doesn't use any of those. So I'm not sure why the BUSREQ signal is being used in Popeye logic.

[@SamsArcadeFix]

Maybe if I knew what the VB signal was or where it comes from would give us a clue. I'll have to look at the schematics and see where it comes from which might give us a clue what it's doing.@@waynegram8907

[@waynegram8907]

@@SamsArcadeFix yes try to look it up to see how they are using the bus request signal