Found the Defender board set, not sure how it got where it was, but I was running out of places to look - side line is that the pile of PCB's is the tidiest it has ever been, and probably the closest to being listed. Got a few unknowns amongst them, so next job may be to romident those and see what they are.
Is it just me, or do arcade boards not make sense - the galaxian PCB from my cabinet decided to start giving me a RAM 3 error. no problem, just check the object ram, and fix that (was the memory select @ 8P), but then also getting a video glitch (dot clocks 5A and 6A) and a ram decode error on the video ram (multiplex at 2E) - but how does a working board fail with 3 separate errors at once! I had heard that sometimes when you replace one chip, the next chip in line then goes, but I can't even see a connection between these three faults. oh well, explains why I seldom get a board with a single fault I suppose.
Almost ready for beta testing on Super Invader Attack, all of the main features are sorted, just need to do some more testing myself, but should be sending out to people before the end of the year.
Almost completed tidying up, and seem to have lost a defender PCB set - not sure how I managed that, it's not as if they are small or anything! Most boards I have to look at are now documented, remainder are really spares boards - so not sure if I should bother with those.
Waiting on schematics for Hot Line pinball, so I can find out why the coin and start buttons don't do anything. Apart from that, it all lights up, and even managed to let me play 1 ball, just to see what it is like. I have plenty of spare parts, so hopefully still on track to have it working and tidied up over the winter.
The year continues flying past!
Stared tidying up the piles of boards, and filling the gaps on the shelf of (mainly) untested PCB's. Also managed to fix a couple whilst doing it which was a bit of a result. A Pacland that has been giving me grief in the sprite priority department finally succumbed to a new ram chip (2049 - took a while to locate one) , and a bubble bobble has finally got the right colours on. Still about half of the shelves to finish, but hopefully by then all of my remaining PCB's will be out of the boxes they were delivered in, and stacked ready for retirement!
Super Invader attack is now fully playable, but no doubt has a few oddities lurking for the beta testers to find. Just need to complete the sounds and complete the integration into the multigame and it should be ready for some serious testing. Discovered why people don't convert games from S2650 CPU's that often - it has more differences from Z80 than I thought, so probably unlikely that I'll attempt any more. Besides Invaders was the only game that I have had continued requests for since I stared this lark long ago *
Also been busy on the pinball front, finally managed to work shop the twilight zone, so that all works and looks nice and shiny. I've now acquired another pinball, a Williams Hot Line, made way back in 1966 - should be interesting trying to get that up and running. I have the aim of getting it fully functional for the 2008 UK Pinball show!
* not strictly true, there's one game that exists on galaxian hardware that I have had more requests for, I'm considering whether to put it in as the 20th and final game for the lineup.
I've been busy recently looking at the long promised 19th game for the multigame. The reason for the massive delay is it's a fairly major amount of work involved as unlike the other games included, it was never converted to galaxian hardware. The hardware it uses however, is very similar capability wise (except for collision detection!), the main problem is that it used a totally different CPU.
So, following the creation of a static re-compiler (takes code for one CPU, converts it to code for a different CPU) here is the first screen shots of the game I am working on ...
As you can see, it started life as the Zaccaria version of 'Super Invader Attack' - which I still think is one of the best (and hardest) conversions of Invaders. Still a long way to go, but the attract mode is basically working. Quite a bit to do before it's ready for inclusion and testing, hope to have it sorted by the end of the year. (I'll need some volunteers for testing, so if you have an eprom programmer and a multigame - send me a mail)
Something I have meaning to do for ages, and I finally got around to it - I have a rainbow island PCB with a blown PAL B22-05 (IC33), and I've always meant to try and reverse engineer a working one to replace it. So, armed with the recent info I obtained whilst fixing another RI, I hooked up the PAL and dumped out every combination of input and output, and then sat down with some paper to work out the equations that would give me the same result. After a couple of 'close' attempts, I eventually managed to re-create the necessary links.
Still got a few other faults before the board is totally working again, but at least I don't have to keep swopping the working PAL between 2 PCB's!
I've been experimenting with an ABI Boardmaster. It's an interesting bit of test gear, very suited to testing boardsets with two or more PCB's where you cannot usually get to one of the lower boards to test components. I used this very sucessfully to locate the rogue chips on the lower board of an IREM Legend of Hero Tomna.
It isn't perfect, and will sometimes identify chips as bad when they are not, but it does give a good pointer for areas to check - especially useful on boards for which no schematics are available.
It was used during a recent weekend meeting to diagnose several faults on a Rainbow Island Extra PCB that otherwise may have been scrapped. for the full story of this, see the repair log!
Multigame prices reduced! - with the current exchange rate, the price of the latest batch of PCB's has gone down, so I have updated the prices to reflect this, and also to reflect the current price of galaxian PCB's
Lots happening on the fixing of real boards, not so much on the high score saver / test board - although the design is completed, and the high score board works fine - no reported faults from any of the beta testers. Maybe my belated new years resolution should be to finally complete it and set up a page so that people can contribute high score savers for other Z80 based games. (in theory, as long as the high score is saved in memory accessed via a Z80 cpu, then you can create a saver using this board - it's also handy for single rom conversions on games that usually use odd eproms)
I've moved a few boards from untested to collection, and still have several to look at whilst I have an ABI Boardmaster on loan. It's an interesting device, tests TTL / RAM etc whilst it's still soldered in to the board, very handy for boards with no schematics. However, it still doesn't make for quick fixes as you really need to test EVERY chip! (and some cannot be tested as other chips interfere with the inputs during testing)
Multi-game is still at 18 games, plans to make this 20 may happen this year, but I think that will be the limit. There's so many 'emulated' multi game boards available now, that the hardware option is really for the hardened gamer only.