- Thread starter frsj8112
- Start date
The test modes on these games are funny and inconsistent, i think you gotta hold start or something when the board is booting as well as the dip switch.
I have a 'test rom' for the 1c and 1b hardware that gives clear ram errors.
It's more work to port to the 1a system (p47) but will have a look sometime as got 2 faulty p47's here that looking at.
A pic of the fault may give some clues, seen B+C hardware do all kinds craziness.
I have a 'test rom' for the 1c and 1b hardware that gives clear ram errors.
It's more work to port to the 1a system (p47) but will have a look sometime as got 2 faulty p47's here that looking at.
A pic of the fault may give some clues, seen B+C hardware do all kinds craziness.
Sprites go down post 6.
On my board there's some toshiba 6116 and a bunch of 157's close to the post, i'd check them first.
After those check the custom, post connections, 6264 rams etc.
This is assuming you have tested with a known good rom board.
On my board there's some toshiba 6116 and a bunch of 157's close to the post, i'd check them first.
After those check the custom, post connections, 6264 rams etc.
This is assuming you have tested with a known good rom board.
I got this board today and trying to figure how to enter in the test menu to see if everything is working (the game seems to run fine from the attract mode). I've tried some combos at startup but only holding the service button I get the squares pattern but nothing else. Am I missin something?
Necro-bump: I have exactly the same issue shown in your video @frsj8112 , but in a Big Striker PCB. Sprites are all purple.
I made a quick visual inspection and piggibacking the sprite ram (2x 6264) but no luck.
Did you managed to solve the issue in your P-47 pcb?
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Show a video of what it does, the test rom is lost in the recent jaleco developments but easy remade
Hey @Hammy, This is the sprite issue: (exactly the same as the previous video of that P-47 pcb. If you look at carefully, you can see that the planes are also purple):
(sorry for the kinda epileptic video... )
Looks like every single color palette index for all pixels in each sprite (apart of transparent pixels) has always the same value (purple color)
I will do further checks on weekend, but my 2 cents are for a bad sram.
Yes, that’s right. At service menu. However it doesn’t find any bad component:
Read the gfx roms and they are also good.
Sprites use the object ram and the back end of the scratch ram so it's most likely a dead line from the object ram's custom to the front area (color ram area) of the board.
Also check around the PROM, if this is bad many strange things can happen on priorities / layers.
Also check around the PROM, if this is bad many strange things can happen on priorities / layers.
Thanks! I'll check it.
Board is in very good condition and at visual inspection I cannot see any damages, scratches or anything that could lead to a broken trace. I also desoldered the PROM to read contents and it matches exactly with MAME dump.
Also, there is no much info about customs in this architecture, even in MAME.
Looks like each scroll layer is managed by the pair of GS90015-02 and GS9000406. Sprites by the pair: GS9000402 and GS9000407
There are also other customs such as GS9000401, GS9000403 and GS9000404 to manage RAMS? and another one (with one sticker on top on it, I cannot read #ref) to manage the color RAMS
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Sorry mate, but I have not resolved the issue.... Don't remember if I still have the pcb.
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