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I bought a cheap ebay famicom copy of gremlins 2 and it contains the sunsoft 5b chip. Would it be possible to convert this into japanese mr. gimmick with the audio wired up?

*edit*

Looking at the maskroms the prg maskrom of gremlins 2 has less pins haha d'oh. I also have a batman return of the joker, would it be easier desoldering the 5b and installing it in my return of the joker nes cart?

Yes.

I'm assuming you mean the Japanese release named Gimmick!, not the PAL release Mr. Gimmick.

You'll need to add the entire audio circuit, in addition to swapping the ROMs: Gremlins 2 doesn't have it (see Gimmick!)

If you do go through with this, we'd be grateful if you'd finish the pinout on the wiki.

Looking at the maskroms the prg maskrom of gremlins 2 has less pins haha d'oh. I also have a batman return of the joker, would it be easier desoldering the 5b and installing it in my return of the joker nes cart?

Given that you're going to have to add the entire audio portion, it won't be "like new" looking... and if you don't have a desoldering station, I would recommend against trying to desolder the 5B. Airwires should be fine.

Yes japanese gimmick!

Here's what I figured out so far with the help of a friend based on gimmick! pcb pictures:

*deleted better schematic posted later*

The capacitor polarity is marked on the gimmick pcb picture but not the rating of the cap, since it's audio line stuff most audio caps are 10 uf from my experience.

Also need to figure out what part of the circuit pins 18 and 3 connect to.

Right now the big concern is the gimmick! pcb has a 32 pin prg maskrom where gremlins 2 only has a 28 pin prg maskrom. I'm terrible when it comes to wiring up nes / famicom carts for eproms.

I can desolder the 5b very safely I have the proper gear.

I previously RE'd the PCB to the same extent you have there, although I have a hunch as to what pins 3 and 18 connect to.

It seems likely that pins 3 and 18 is some kind of amplifier, it would be nice to test that. Hopefully those pins in In the Gremlins cart are floating; you should be able to use a 100k pullup/down or something on each of the pins and see if the other is driven the opposite way.

Drakon wrote:I can desolder the 5b very safely I have the proper gear.

Fair enough. I'd like to encourage you to not destroy two cartridges to make one, but they're yours and I can't usefully say anything stronger.

What do you suppose the compatibility of this pirate cart is?
http://www.ebay.com/itm/Gremlins-2-Fami ... 3ccd7527c9

mikejmoffitt wrote:What do you suppose the compatibility of this pirate cart is?
http://www.ebay.com/itm/Gremlins-2-Fami ... 3ccd7527c9

Haha probably not the greatest.

lidnariq wrote:Fair enough. I'd like to encourage you to not destroy two cartridges to make one, but they're yours and I can't usefully say anything stronger.

Believe me I'd much rather get this working in the gremlins cart I'm just not sure how much of a pain it is. Anyway I socketed the maskroms:









If I ever get this thing converted to gimmick I'll probably just hard solder in the eproms. These sockets are just for now. I need to order the right eproms to burn gimmick. Then I'll need to figure out the wiring....bleh...

グレムリン Gremlin in that logo looks dangerously close to グレムリソ Gremliso. In katakana, where does ン n become ソ so and ソ so become リ ri?

Anyway if someone could help me figure out the eprom wiring for this thing that would be much appreciated.

tepples wrote:In katakana, where does ン n become ソ so and ソ so become リ ri?

Direction of stroke may help you think about how these are distinguished.

so
n
ri

You can see that ン is dominated by left-to-right strokes, but ソ and リ are top-to-bottom. When written with brushes, the direction of stroke can usually be seen clearly (the Gremlins title screen tries to show a bit of stroke shape). It's harder to capture this in a small bitmapped font, but at least you should try to emphasize the horizontal orientation of ン to distinguish it from ソ.

The small stroke in リ should be vertical and slightly longer compared to the more diagonal stroke in ソ. Its long stroke is also more vertical than in ソ and does not usually extend as far left.

Context also helps disambiguate, as always, but sometimes ソ and ン are just going to mistaken for each other. There's probably an opportunity for a visual puns there too, but my grasp of the language is nowhere near strong enough to think of those.

Drakon wrote:eprom wiring

http://wiki.nesdev.com/w/index.php/Mask_ROM_pinout

lidnariq wrote:

Drakon wrote:eprom wiring

http://wiki.nesdev.com/w/index.php/Mask_ROM_pinout

Yeah I'm a bit mentally handycapped with this. Sopposedly the eprom for the gimmick prg is going to be 32 pin and it's 256k, but the gremlins 2 pcb only has a 28 pin spot for prg which is 128k, would it be possible to wire that up?

Yes, it's doable.

Unfortunately, I'm not willing to give you a guide.

lidnariq wrote:Yes, it's doable.

Unfortunately, I'm not willing to give you a guide.

I don't mind as long as I know it's possible. I did a bit of research on it. My batman return of the joker pcb is wired up with the same pinout as 27c010 / 27c020 eproms. I desoldered the maskroms, dumped them, downloaded the rom of the game from the net, split the downloaded rom into chr and prj, and the crcs of the split files are identical to the maskroms I dumped. That's interesting this batman return of the joker fme7 pcb is wired for you to burn and drop in an eprom with no rewiring it seems.

The gremlins 2 famicom pcb is wired up for nes maskrom pinout so once I get some eproms I'll need to rewire it.

Sometimes even Japanese people screw up their own language, just look at filenames like "kikkomaso.swf" instead of Kikkoman.

Okay I looked at the gremlins 2 pcb. The chr maskrom is eprom compatible. I dumped the chr maskrom with my rom dumper without any rewiring, downloaded the gremlins 2 japanese rom, split the japanese rom, and the crc of the downloaded chr is identical to the crc of the dump I made using the maskrom. The gremlins 2 prg rom is nes wiring, not eprom compatible, so that'll require rewiring, and then there's the issue of wiring up a 32 pin eprom into a 28 pin socket.

*edit*

Okay I got the wiring figured out. Besides changing the wiring for the 32 pin eprom to work in the 28 pin spot I'll also need to connect a17 from the eprom to the prg a17 pin on the 5b chip. Hopefully this works.