Sega VIC Dual Timing PROMs (Memory and Video issues)

SNESNESCUBE64

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I have a Sega Vic Dual PCB on my bench right now that is throwing me for a loop right now. So I confirmed that I can read ROMs just fine on this but I had no video and was running into odd ram issues. I validated these things using my fluke.

The first thing I did was validated was the PROMs themselves. I have several sets on hand because I've had to do VIC dual stuff before. For this excercise I used the timing PROMs from Samurai and Wanted. My test PROMs validated just fine on my superpro. The problem I noticed though is that SRLD is always high. This is responsible for generating the clock signals used by video. I've confirmed the write signal to the 175s (this is the 15.something MHz base clock) to be fine. This is a snippit from Borderline's manual, as this is the best copy I can find of the two PROM version of the VIC hardware.
image-78.png

Does anyone have any insight as to why I might be encountering these issues? I believe that the 175s are good. I am just not understanding why I might be missing the clock signals here.
 
Which schematics are you using?
The VICs I've dealt with don't have feedback like that:

It looks like your schematic is doing the doing the div24 with the PROM and the 175s instead of having the LS74 + LS163 external.

If your PROMs are good then it pretty much has to be U21/22.
Probe through the counters and make sure the div24 (up to M4) is working right.

1744914890767.png
 
Which schematics are you using?
Sorry for missing this post. I am using the schematics found in Borderline's manual.

I have some S175s on order, just haven't gotten them in yet. I swapped them with a couple used pulls but lord knows where these ones came from. But that is what is throwing me for a loop, if MUST be the PROMs or 175s but they are all testing good.
 
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