Space Firebird (Bootleg) Repair - Part 1

Another Nintendo board for repair and the collection, I got this in a trade a good while back but have only just gotten around to making a jamma adapter and testing it. When doing a google search for a pinout a ukvac thread comes up where someone says that it's the same pinout as Phoenix, that isn't quite the case but more on that later.

When powered on I got an explosion sound and a starfield and not much else. There were a few dots and lines that were meant to be sprites. This turned out to be a bunch of bad 2101A rams on the video board, thankfully they're all socketed and I am able to test each one out of circuit in the Boardmaster. All but two failed, AMD branded.

I've had issues with AMD branded logic in the past too, maybe they should have just stuck to CPUs.😄

New RAMs fitted. This brought the sprites back and showed a new issue. All the bullets were on the very bottom of the screen under the player ship.

I went looking for counters on the video board, there's some very nice quality schematics for this board online which is a nice change from the usual no schematics or unreadable schematics.

Piggybacking didn't work but using a logic probe I could see the outputs on 74161 @ 4G were all shorted to ground, which also explains why piggbacking a good 161 on top didn't work.

 

Unusual brand of TTL on this board that I don't recognise which is usually a bad sigh but they work for now.

That fixed the bullets issue, a very hard game to photograph as it turns out.

 

 I took 40 pictures and that was the best of them.

 

That's all for now, I'll have to return to it at some point to see why I only get explosion sounds and the rest of the time it's completely silent.

Here's the pinout.

 

This is not at all the same as Phoenix pinout, the controls and video are on opposite sides, you also need -5v for Space Firebird as it has its sound data stored on a 2708 eprom.