UNROM -> AOROM conversion (mapper 7) Question
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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
2. No advertising your reproductions, with the exception of free software.
3. Be nice. See RFC 1855 if you aren't sure what this means.
UNROM -> AOROM conversion (mapper 7) Question
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.
Last edited by Tormenter on Fri Jul 28, 2006 12:28 pm, edited 1 time in total.
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)
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%20Conversions.txt
Even though it states CNROM is mapper 3? Im confused lol. Thanks!
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.
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.
Useless, lumbering half-wits don't scare us.
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.
Useless, lumbering half-wits don't scare us.
Re: UNROM -> AOROM conversion (mapper 7) Question
I 've been trying to make Battletoads Famicom for days.
I removed '32
Lifted 6 pin '74 and connected to 18 pin 27c020
Connected 11 pin '74 to 18 pin cartridge (CIRAM A10)
Connected 3 pin 27c020 to 11 pin '74
Connected 2 pin 27c020 to 13 pin '74
Connected 30 pin 27c020 to 12 pin '74
Connected 24 pin 27c020 to 16 pin 27c020
Connected 1 pin 27c020 to hole 1 pin prg
But nothing works. Where did I make a mistake?
I removed '32
Lifted 6 pin '74 and connected to 18 pin 27c020
Connected 11 pin '74 to 18 pin cartridge (CIRAM A10)
Connected 3 pin 27c020 to 11 pin '74
Connected 2 pin 27c020 to 13 pin '74
Connected 30 pin 27c020 to 12 pin '74
Connected 24 pin 27c020 to 16 pin 27c020
Connected 1 pin 27c020 to hole 1 pin prg
But nothing works. Where did I make a mistake?
Re: UNROM -> AOROM conversion (mapper 7) Question
Why are you using a 74'74? AxROM does not have any but a 74'161 (and eventually a 74'02 for ANROM).
Either way, here's the pinout:
Either way, here's the pinout:
Code: Select all
74'161 74'02 (ANROM only)
__ __ __ __
VCC |01\/16| VCC 1-12 |01\/14| VCC
/ROMSEL |02 15| NC CPU R/W |02 13| 8-9-13
CPU D0 |03 14| PRG A15 PU R/W |03 12| 1-12
CPU D1 |04 13| PRG A16 NC |04 11| /ROMSEL
CPU D2* |05 12| PRG A17* GND |05 10| PRG /CE*
CPU D4 |06 11| CIRAM A10 GND |06 09| 8-9-13
GND |07 10| GND GND |07 08| 8-9-13
GND |08 09| CPU R/W ------
------
*
AMROM:
CPU D2 = Connected
PRG A17 = Not Connected
PRG /CE = Not Connected
ANROM:
CPU D2 = Not Connected
PRG A17 = Not Connected
PRG /CE = Connected
AOROM:
CPU D2 = Connected
PRG A17 = Connected
PRG /CE = Not Connected
Re: UNROM -> AOROM conversion (mapper 7) Question
Sorry I was wrong while I wrote. Of course I use 74 '161Ice Man wrote: ↑Thu Mar 19, 2020 1:01 pm Why are you using a 74'74? AxROM does not have any but a 74'161 (and eventually a 74'02 for ANROM).
Either way, here's the pinout:
Code: Select all
74'161 74'02 (ANROM only) __ __ __ __ VCC |01\/16| VCC 1-12 |01\/14| VCC /ROMSEL |02 15| NC CPU R/W |02 13| 8-9-13 CPU D0 |03 14| PRG A15 PU R/W |03 12| 1-12 CPU D1 |04 13| PRG A16 NC |04 11| /ROMSEL CPU D2* |05 12| PRG A17* GND |05 10| PRG /CE* CPU D4 |06 11| CIRAM A10 GND |06 09| 8-9-13 GND |07 10| GND GND |07 08| 8-9-13 GND |08 09| CPU R/W ------ ------ * AMROM: CPU D2 = Connected PRG A17 = Not Connected PRG /CE = Not Connected ANROM: CPU D2 = Not Connected PRG A17 = Not Connected PRG /CE = Connected AOROM: CPU D2 = Connected PRG A17 = Connected PRG /CE = Not Connected