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Found a really small mistake with my U33 replacement. I am going to have to go back to the drawing board.

I thought this PCB of mine had a defect, because it would have corrupt text only during the ending credit sequence, after the game is cleared. This happens when text is scrolled to an odd offset. I figured it was a bad 74LS157 in the text section, or the select signal is bad, since it swaps even and odd columns.

After trying in vain to find a bad IC on the board, I finally burned myself a hacked ROM that would offset the text by one pixel, so it is generally always at an odd offset. And...


CQTBeLx.jpg



Unfortunately by swapping the GAL with an original I can confirm this is caused by my incomplete reproduction. I'm going to have to figure this one out.
 
nice iv been following this as my boot has the weird offset with text in Settings and on one scene demo screen
 
Alright, got it fixed in a few hours after comparing with an original chip.

Updated .eqn files and pushed to github the .jed as well. Pictures show the signal transition I had missed in the abnormal case.
 

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