The Invaders Zaccaria

[PaTrYcK]

New comer, The Invaders Zaccaria, 1979!

Cab complete and in good condition but will be a long restoration 

[PaTrYcK]

Hi, today i check board game, usually i see that there are 2708 in pcb, instead there is satellite board with prom...

[PaTrYcK]

The restoration goes on,  pcb have some problems:




http://www.youtube.com/watch?v=V9saFvGeAZE


now my friend Piero work on pcb the invaders, some ram have been replaced:



now the situation is better not yet fully functional, the problem could be in the prom on satellite board, someone have dumped it?

[PaulSwan]

What's left doesn't look like a PROM problem, more like a video address problem from the video counters given it looks like you have a repeated screen.
Paul.

[piero.a]

What's left doesn't look like a PROM problem, more like a video address problem from the video counters given it looks like you have a repeated screen.
Paul.

Hello Paul,

I absolutely agree with you but which is the video address decoder?

Schematic seems to be unavailable. All video ram are tested and good.

May be the BPROM 6/82S140 involved on video addressing?

I dumped IC6 (82S140) and 31 (82S190) but I haven't a good dump to compare because both are not present in mame dump.

I'm unable to use my fluke (and 2650 adapter) because bus test fail (Data bit 0 and 2 or 7 tied low). I have the same issue on Astrowars and quasar but I solve the problem pulling out the 74LS244 (13E on astrowars and 3G on quasar) just to make ram/rom testing

I guess that there's a more elegant solution

[PaTrYcK]

My friend piero fix pcb zaccaria, buffer 40097 faulty...

Now is ok!

http://youtu.be/BuiqpNkBMu4

[blackie63]

thats some good work getting it up and running correctly