At the start of the game Kong climbs a ladder, the sprite was messed up, Mario looked weird when moving like he had a broken leg and when he got to a certain point on a ladder he turned into a blue ladder.
After ruling out the usual suspects (bad traces, eproms and fujitsu ttl) I was left looking at all the other ttl, and there's a lot of it. The Gauck comparator probably would have saved me an hour or so but unfortunately I haven't even started to build it yet.
Since the fault isn't constant it was tricky to track down, I decided to crash the game at a point where it was glitched, I did this by bridging two address lines on the Z80. Then went around the board with the logic probe and hp comparator, I eventually found a 74LS273 @ D2 with output pin 16 stuck low.
It's not a Fujitsu for once.
I replaced the 74LS273, Kong is now restored and Mario can run and climb ladders without disappearing once again.
This just left the sound issue which was a simple one, I replaced the AY-3-8910 chip and all sound was restored and played correctly.
Hi, I have a crazy kong that just started having similar problems to this.Kong is missing and is random vertical lines. jumpman and the barrels only show up at the very bottom of the screen and then it's only half of them. As soon as I go up a ladder jumpman vanishes but I will still die from hitting the barrels. I checked the roms in mame and they look ok. Do you have any ideas what I should look at, I was thinking about swapping the 2 ram chips.
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