Supergun
Student
Yes. I just checked this and I can confirm that it is toggling.In the meantime can you confirm pin 25 (A8 of 16C is now toggling?
Now just to get the output enable on Rom 15C to work. In the mean time can you probe the ram? I think its the 6264 Ram according to mame source code. Pin 1 is n/c or should be. Doesnt matter what logic level it is. All address and data lines should be toggling. Gnd low, Vcc high. CE OE and WE should be toggling as that controls if the ram is being read or written too
Yes as well. I just confirmed the 6264SL ram at 14C is acting just as you describe above. All address lines are toggling, the ground pin is low and the the vcc pin is high.
However, there is another 6264 ram at position E by the edge of the board. It is a different package as well. So should I probe that one as well?
EDIT: A quick probe of that ram chip showed everything the same with 2 exceptions; Pins 20 and 26. 20 was low and 26 was high.
What are the changes on screen now that 15C is working
Well, different garbage on screen but still garbage. It does tend to move and roll more often now however. I will post some screen shots shortly.
EDIT: just to answer this question here:
“…that LS138@14A: Double check if you got probe set correctly and confirm if all pins are high except ground on pin 8? You mentioned pins 4 and 5 connects to Konami Custom chip 007842? There isn't such thing. Did you mean the 007327 ?
This was my mistake. I read the chip number from the chip surface which as you can see looks like it says 007842. However, if you look at the silkscreen on the PCB, it is 007342. So I simply misread the 3 as an 8 because it is so faded on the chip itself.
As for the LS138, it now reads as follows:
Pins 1, 2, and 3 are BOTH and Pin 8 is LO. All other pins are HI.
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