Jungle Hunt with new RAM

priglmeier

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Status -

I have a JH PCB with new RAM and about 12 new caps. All the removable chips have been reseated. The power supply and hookup is JAMMA and is working fine.

Problem -

I am still getting bad graphics and text.

Testing -

I used the 'test' DIP and I get a blue screen with text like this... see picture. (Looks like backwards black 'F's on a white text block with blue background)
I also tried swapping RAM just in case with no change.

Thoughts?!?

I am thinking it's time for a new set of graphics EPROMS. I am able to play the game with sound, but the graphics are garbled.
 

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Have you tested your voltages to make sure they are good? Could be a rom issue, are the roms legs clean and sockets feel tight?
 
options?

Everything is connected well and looks fine. The cost to have the GFX1 set of EEPROMs burned is $40 and $100 for the entire set. I'm not sure what do do from here... that's a lot to invest in this PCB when I could find another one cheaper. Unfortunately, there would be one less JH PCB in the world.

Can anyone else burn EEPROMs cheaper? Other options?

thanks
 
Everything is connected well and looks fine. The cost to have the GFX1 set of EEPROMs burned is $40 and $100 for the entire set. I'm not sure what do do from here... that's a lot to invest in this PCB when I could find another one cheaper. Unfortunately, there would be one less JH PCB in the world.

Can anyone else burn EEPROMs cheaper? Other options?

thanks

If ALL your graphics AND text are bad, I would find it unlikely that all your gfx roms are bad. More likely its a problem in the addressing or shift registers on the data bus of those EPROMS...
 
I have gotten the text be be ok. Now the graphics are worse. I did find that some of the EPROMs do have the labels in the opposite direction and that has bit me a few times as I have swapped / reseated chips.

I am weighing my options now.
 
oddities

Make sure no chips are installed backwards?

I did find some chips backwards. The labels were upside-down and mostly covering the chips.
Fixed that... then cleaned the entire PCB, reseated chips and got a better result with the Jungle hunt title screen and text. The game graphics aren't good though and now I have some RAM errors:

85FF
86FF
86E3
86E9
87f7

The problem is that it doesn't specify the ROM, just the memory address. How do I know which chip is dirty, socketed poorly or bad???
 
I did find some chips backwards. The labels were upside-down and mostly covering the chips.
Fixed that... then cleaned the entire PCB, reseated chips and got a better result with the Jungle hunt title screen and text. The game graphics aren't good though and now I have some RAM errors:

85FF
86FF
86E3
86E9
87f7

The problem is that it doesn't specify the ROM, just the memory address. How do I know which chip is dirty, socketed poorly or bad???

You do realize that the chips that were installed backwards are now bad don't you??????
 
Usually they are toast...

If the EPROM got really hot when plugged in backwards there's a good chance it'll still work. If it's cold and plugged in backwards then the teeny wires you see going to/from the chip in the window that carry power have burnt like fuses.

RJ
 
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