Uniwar S bootleg

[Lurch666]

This was supposed to be a uniwars s:

After wiring up an adapter and getting nothing research found it to be a bootleg.I changed the wiring for moon cresta and that got this board to the fault that the previous owner described.

It shows moving graphics that look like the self test,then I briefly got 'BAD RAM 3' then it would reboot and repeat.

After messing around with the memory (2114s) I ended up trying Philmurrs galaxian test rom.That worked and passed all the tests but on putting a galaxian bootleg (galaxianbl in mame) onto it I was still getting the bad ram problem.

From experience with my scramble pcb I tried different roms and eventually found a pacman bootleg would work.Now the graphics aren't working properly-It doesn't seem to be selecting the two pairs of roms on the daugterboard properly but I'm not to bothered about that at the moment.

There is also the problem of the screen being upside down and the pacman and ghost sprites sometimes jump vertically down so they are out of position then they will jump back again.This seems to happen at specific points (only watched in demo mode) so I'm thinking this is a ram problem even though the board has passed the ram tests.

I'm thinking if I can get this sprite problem fixed then the uniwars s might boot as well.

Also am I correct in assuming this board IS a moon cresta boot?

 

[philmurr]

It's a generic "Galaxian" bootleg that a load of games were hacked to run on.

Odd that the test ROM passes the RAM tests but you still get BAD RAM 3 error, I can't explain that.

The test ROM doesn't test the sprite RAM (other than showing the 7½ sprites falling from top to bottom of screen) because the CPU can't read that memory back. You'll need to troubleshoot the sprite circuit, look at the schematics to the right of 6R - if it is a sprite problem it's likely to be somewhere there.

 

[Lurch666]

are there schematics of this board?I thought bootlegs were hard to find diagrams for.

I'll go and have a google.

thanks dude.

 

[deano76]

Was this the PCB that was on eBay recently ?

I've a PCB the same and was struggling to ID it, seen the eBay listing by chance and thought oh nice I've a Uniwar S here !

It's a generic "Galaxian" bootleg that a load of games were hacked to run on.

Odd that the test ROM passes the RAM tests but you still get BAD RAM 3 error, I can't explain that.

The test ROM doesn't test the sprite RAM (other than showing the 7½ sprites falling from top to bottom of screen) because the CPU can't read that memory back. You'll need to troubleshoot the sprite circuit, look at the schematics to the right of 6R - if it is a sprite problem it's likely to be somewhere there.

Glad you've mentioned that its a Galaxian boot of some sort

The PCB I've got, the EPROMS are labelled up as "FROGS" ???

 

[Lurch666]

Yep got it last week.

I have just tried a moon cresta bootleg and got that working although the daughterboard with the graphics rom is still messing up.

I wonder if that mod (4 sets of 2716 instead of 2 set of 2716 eproms) is specific to uniwars.

Anyway on moon cresta it's still upside down and the smallest ship moves with the same glitches as in pacman BUT when I swapped the 2101 chips it still glitches but in a different way.Got some 2101s coming (from America) so that might solve the bad ram 3 problem.

Still can't find any specific schematics-just the standard galaxian.will it be the same as my boot?

Lurch6662017-12-09 18:41:04

 

[Lurch666]

Well that's the advantage of working on multiple boards at the same time.

You can see from my other threads I am also working on a wonderboy in monsterland and a Zaxxon.

While I was checking out my Zaxxon I noticed two socketed chips that looked similar to the ones at 4F and 5F on my uniwars.

Looking on the net I discovered they were equivalent so I tried swapping them around and found the ones on my Zaxxon fixed the sprite jumping on my uniwars (still running moon cresta at the time) but the chips from my uniwars made my Zaxxon worse-the sprites disappeared.

So since I had fixed the sprite jumping I put the uniwars roms back in and now it runs.Watched in demo mode as I don't have any controls wired up yet and the game looks fine.

So if you have one of these bootleg boards coming up with a 'BAD RAM 3' or sprite problems change the chips at 4F and 5F.

Will test the full game and sound tomorrow.