Hi!!
I want to build a cartridge with original Holy Diver
. I think, it is possible to do on an UNROM board. But, I don't know what's really needed to build a cartridge..... Can someone tell me about this??? Or can someone make a full pinout??? I will be very thankful!!!
As I suggested to you in private, with a UNROM board (Max PRG Size of 128Kb) the game will run. There are two other things you need which will require modding the UNROM board. You need CNROM style CHR switching using D4,D5,D6,D7. Then you also need Mirroring Control by D3, 0 = Horizontal Mirroring, 1 = Vertical Mirroring.
WOW!!! I recorded an original holy diver PRG on my EPROM 128KB, I've started it on my UNROM dev-cart and i can really play it!! But with crappy graphics, of course
. But, I don't really understand you..... CNROM can address max 32KB CHR and there is a full pinout of CNROM board:
and there is D0, D1, D4 and D5 connected from 74LS161 but to the PRG ROM. So, can someone make a full pinout, how to connect CHR ROM???
You should probably add another 74LS161 to the UNROM cartridge and connect it like in that diagram except you need to use PRG D4, D5, D6, and D7. Then connect CHRA13, A14, and under those two I imagine you should put CHR A15 and A16.
That should get you most of the way there. The only other thing to do is work out mirroring. I'm not sure how you could control that with a 74LS161 but it can be done. All I can say is Holy Diver expects D3 as the mirroring bit. Maybe someone else can give you more info.
i thought this was mapper 1? why not just use a SLROM board. they are very common
I think it was hacked to use mapper 1. It's probably easier to use the hacked version than to modify the hell out of the board.
tokumaru wrote:
I think it was hacked to use mapper 1. It's probably easier to use the hacked version than to modify the hell out of the board.
YES, but, this version is buggy....
The MMC1 hack I did has two issues. One is somewhere a bug exists that prevents the player from using the Twin Fireball magic and causes problems with the first boss and possibly after that. I could probably fix it but there's another issue which is massive slowdown because the game had very little free processing time free to begin with. Normally it takes quite a bit of action to cause slowdown but when using a mapper like mmc1 or mmc3 the time spent writing to registers is too much. I might be able to optimize it a bit but it seems to me it would be easier to just modify UNROM to work like mapper 78.
YEAH!!! Big thanks guys!!!
I connected CHR with another 74LS161 from this diagram, but to PRG i connected D4, D5, D6 and D7 pins
.
Now I made a dev-cart. If something will be wrong, I will rewire this
.
(this is a pirate famicom cart with UNROM board
)
And original IREM's holy diver really works with graphics!!!
But..... on the first level graphic is crappy.......
so, how to control the mirroring??? Please, help me, I will be VERY thankful!!!
There should be H and V pads on the board which are shorted together for Vertical or Horizontal mirroring. You'll have to take the signal from these pads and figure out how you hook it up to one of the output bits on the LS161. D3 is supposed to be used to switch mirroring on Holy Diver. When D3 is = 0 it is Horizontal Mirroring, when 1 it is Vertical Mirroring.
I do not fully understand mirroring on the hardware level as far as what is going on so I can't really speculate how you use the D3 bit to set mirroring. Other members will though.
The only discrete mapper with a mirroring switch that I know of is A*ROM, which uses single-screen mirroring. One would need a mux to implement MMC1/MMC3 style mapper-controlled mirroring.
Why the need to create a repro in the first place, is the original hard/expensive to find?
In that case, why the need to repro instead of importing an authentic cartridge and breaking open a R.O.B. cartridge for the NES-JOINT adapter?
it goes for like 40 bucks on ebay, that's too much.
The real price is more like 10$. If you can find it loose, even less.
where u gonna find that in non Asian country's?
That's when it get harder to get it. I was talking about the original price in japan when I got it. In some specialized shop, it will be more expensive. the only way to have it cheaper it to have a contact in japan that can find it loose. The price may have increase since I bought it (2004).
edit:
Just one random place that I found it at 10$:
http://kakaku.journal.mycom.co.jp/item_ ... 80153.html
Some place are 20$ or a little bit less. It depends where you get it. One auction guy is selling it in a lot with batman/raf world starting at 5$
http://www.mbok.jp/item/item_216901614.html
edit2:
Another link, loose, 5$:
http://item.rakuten.co.jp/hontonosouko/gf-706/
So 40$, that's too expensive. It's not that price at all. Ebay it not the best place to get stuff unless you know the real price of the thing you're looking for.
Edit3:
Another shop, 4.80$
http://www.geo-online.co.jp/ds/0003002/
If I where in the market for the game, I would find it hard to order from one of those shops............
Of course. If you don't understand japanese you cannot order and most shop will not ship oversea anyway.
The point was that the actual game is not that expensive. Asking 40$ for it is too much when you know the current street price in it original market. The links were just to show as an example the current price.
YEAH!! I've nearly done it!!!
But, nearly.....
Don't look up at the early photos, because i haven't cutted some tracks on this pirate PCB and graphics was really crapped
.
Some new screens with beautiful graphics from original IREM's Holy Diver
:
And I connected an extra 74LS00 chip like on this scheme by kyuusaku , but, I think, the mirroring is still wrong, just look on those photos...... And after removing this 74LS00 , the IREM screen and title screen is f*cked, but, the graphics on first level is better a little.....
And, AOROM board has got single-screen mirroring, but nestopia says, the holy diver uses four-screen mirroring..... So, change something??? Add something???
Well I only guessed about the mirroring. I still think it's two-screen, so just swap the wires to PPU A10 and PPU A11.
OK. I swapped those wires and graphics are worse than before.....
Heh OK, then it must be one-screen mirroring, try connecting the Q3 output directly to VRAM A10. I really don't think it's four-screen so if that doesn't fix it, there must be a problem with your wiring of the 7400.
Guys, I want to continue creating this cart now. Finally, now on bootgod is original holy diver cart!!!:
http://bootgod.dyndns.org:7777/profile.php?id=4038
So, on this PCB there are 2x 74HC161, 74HC32, 74HC00 and 74HC245 chips. So, there is an extra 74HC245 chip, so, anybody know, how to connect this chip???
The 245 is buffering the CHR data bus, but it's not immediately apparent what enables the buffer. Perhaps they used a very slow ROM or the ROM has only one enable, so they tied it enabled and the 245 is used for output enable (A13 || /RD). It doesn't really matter, you don't need it if you used a JEDEC EPROM and tied /OE to /RD and /CE to A13.