I know you can convert an Unrom/Mapper 7 cart (7 - 74HC32). I am attemping to make a Goonies 1 cart. But the problem is, There is both a PRG AND CHR file with this, but the AOROM conversion only talks about the PRG chip slot. Any clues? Thanks Bunches.
AOROM which is mapper 7 doesn't have a 7432 (OR gate) because it has no static bank.
Goonies 1 is a CNROM in the US AFAIK
AOROM doesn't have CHR ROM, it has CHR RAM.
To convert a UNROM (must be 128kb) to AOROM (must be 256kb) you must simulate a static bank by dividing the game into 16kb blocks and append the last bank (bank 7) to each of the banks including bank 7. The file size should be 256kb. You must then modify the AOROM board by cutting the line from D4 of the 74161 and solder that line (VRAM A10) to CHR A10 if it has vertical mirroring (horizontal scrolling) or CHR A11 if it has horizontal mirroring (vertical scrolling)
kyuusaku wrote:
To convert a UNROM (must be 128kb) to AOROM (must be 256kb) you must simulate a static bank by dividing the game into 16kb blocks and append the last bank (bank 7) to each of the banks including bank 7. The file size should be 256kb.
.....you lost me. lol Im not that technical into these type of things.
The PRG is 32k, and the CHR is 16k.
So I would use the CNROM board then correct? Even though it says goonies is "Memory Mapper: 7 - 74HC32?"
And CNROMS require no modifications per
http://nesdev.com/NES%20EPROM% ... rsions.txt
Even though it states CNROM is mapper 3? Im confused lol. Thanks!
Who said Goonies was mapper 7? and who said mapper 7 even had a 7432? Mapper 2 (UOROM) has a 7432 and 74161, mapper 7 only has a 74161.
Yes Goonies is CNROM aka mapper 3. That's right, you won't need to modify the board in any way, just swap out the ROMs.
This is what it says in cajoNES anyways. (or the rom I have is) Is this not a correct one?
found another copy that says 3 - VROM switch ???
Tormenter wrote:
found another copy that says 3 - VROM switch ???
That's the one you want, then. Wow, "VROM Switch", haven't seen that term in a while. I think that's what NESticle called mapper #3 (CNROM).
The first Goonies game has been only released in Japan officially, using a discrete logic maper made by Konami, similar to CNROM, but using its register in $6000 range instead of $8000-$ffff
There is a hack of it using mapper 3 floating arround, that avoid bus conflicts correctly, so it can be used on a real mapper 3 hardware.
Would it matter if it was a CNROM-256-05 (Tiger Heli) or a CNROM-06 (Back to the Future) or is there a difference??
Look yourself for differences. Normally there shouldn't be much difference, but the solder pads can be different for mirroring and PRG/CHR repeating.
Bregalad wrote:
Look yourself for differences.
I tried, hince, thats why I am asking. Im not a techie.
Well, you don't need to be that much technical. Just look the PCB and notice what is different on them. Sometimes there is minor details, such as additionnal capacitors or resitsorts that have some noise-immunity issues, or solder pads that are different (this is significant for Name Table mirroring). Other than that, most difference between PCB variants are unsignificant.