- Joined
- Nov 29, 2005
- Posts
- 4,316
Here's a tidbit from my repair logs tonight. This cart was one I traded a forum member for. It turned out to have 2 bad ROMs in it and was fixed. I converted it to USA region, but WOW, the US version sucked compared to Japan's.
Since it was mine, I figured I'd experiment with putting two ROM images on a chip and switching between them using a simple SPDT switch.
Enjoy!
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Model: F3
Tip: Making a multi-region cart
CAUTION: Be careful wiring the switch! If you miswire it you could create a dead short between +5v and ground which could damage the cartridge and/or game board. DO THIS AT YOUR OWN RISK.
Some carts look MUCH better in Japan region than they do in the US region: Puzzle Bobble 2 is an example of one. To change the region one must change the last byte of the right most EPROM so to make a dual region cart, simply use an EPROM that is 2x the size and copy/edit the code.
The Puzzle Bobble 2 cart uses a 27C020-12 EPROM. Read the right most EPROM into your programmer. Copy the code region from 00000 to 3FFFF and paste it into region 40000 to 7FFFF. Next edit the byte at 7FFFF and change it to 02 for the US region. Program it into a 27C040-12 EPROM and verify it. Next, mount a SPDT switch to the top case of the cartridge. Wire one outside contact to +5v and the other to ground. Take the EPROM, bend pin 31 out straight from the body of the chip and trim the skinny part of the leg off. Solder a wire from the uppermost address line which, in the case of the 27C040, is pin 31 to the center contact of the switch.
To run one region, flip the switch then power up the unit. To change regions, turn the game off then move the switch to the other position and power it back up.
DO NOT flip the switch while power is on. It could crash the game - but won't cause damage. You WILL need to reset the backup data when changing regions, just like you would if you switched carts on the F3 system.
Since it was mine, I figured I'd experiment with putting two ROM images on a chip and switching between them using a simple SPDT switch.
Enjoy!
---------
Model: F3
Tip: Making a multi-region cart
CAUTION: Be careful wiring the switch! If you miswire it you could create a dead short between +5v and ground which could damage the cartridge and/or game board. DO THIS AT YOUR OWN RISK.
Some carts look MUCH better in Japan region than they do in the US region: Puzzle Bobble 2 is an example of one. To change the region one must change the last byte of the right most EPROM so to make a dual region cart, simply use an EPROM that is 2x the size and copy/edit the code.
The Puzzle Bobble 2 cart uses a 27C020-12 EPROM. Read the right most EPROM into your programmer. Copy the code region from 00000 to 3FFFF and paste it into region 40000 to 7FFFF. Next edit the byte at 7FFFF and change it to 02 for the US region. Program it into a 27C040-12 EPROM and verify it. Next, mount a SPDT switch to the top case of the cartridge. Wire one outside contact to +5v and the other to ground. Take the EPROM, bend pin 31 out straight from the body of the chip and trim the skinny part of the leg off. Solder a wire from the uppermost address line which, in the case of the 27C040, is pin 31 to the center contact of the switch.
To run one region, flip the switch then power up the unit. To change regions, turn the game off then move the switch to the other position and power it back up.
DO NOT flip the switch while power is on. It could crash the game - but won't cause damage. You WILL need to reset the backup data when changing regions, just like you would if you switched carts on the F3 system.