I am looking at schematics for the SGB and I am looking at the circuits on the unit but I have no idea where to add a variable clock mod onto the unit. I wanna add a dial on it but I dont think the SGB has a crystal on it at all.
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Kyle, Tx
No, I want it on the cart. I have seen a couple of them but noone is kind enough to share how they did it.
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Alive and well in fucksville
the output has to override the signal going to the clock. you need a ground, +5v, and an output. I used an old ltc 1799 from getlofi without a resistor... it crashes sometimes. i have never worked with a v2 though. it may be better. if there is no clock signal i dunno what to tell you. maybe try power starving it. i have done no such thing though.
Last edited by bitjacker (Jul 22, 2013 4:20 pm)
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Kyle, Tx
I wish NeX would fix his blog
http://nex.gg8.se/modblog/2010/04/pitch … r-gameboy/
I would be set and ready to go hahah
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The SGB has a pin where it derives the Gameboy clock frequency based off of the SNES one. Check the pinout for a clock pin, follow the traces, cut the trace somewhere. Yank out a DMG CPU crystal, wire it in for precise speed, install a clock kit much like you would a DMG.
The SGB doesn't need the SNES clockspeed, it was just convenient for Nintendo to create a near-identical signal using the SNES clock send signal. It isn't crucial that this signal be present, but you need a suitable one to replace it.
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Kyle, Tx
Ah perfect do you find the clock pin and bridge it with standard operations. I was wondering why there appeared to be only one.
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Alive and well in fucksville
some varible clocks are powerful enough where you dont need to cut the trace.
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Austin, TX
I've done this mod, but I followed NeX's method... All I can remember off the top of my head is that you have to locate the clock trace on the SGB and cut it. Then put a toggle switch that can connect the two point of the trace you just cut, and have the other position of the switch going to var. clock. I wish I could explain it easier, but since there aren't too many tutorials for this mod, I'll do my best to put together one together.
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Kyle, Tx
Thanks I think I grasp the concept. I will have to go get some switches and make a tutorial myself if I get the time here soon. If not I will make a tutorial regardless.
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Austin, TX
defPREMIUM wrote:
boddah ur avatar is different!
Indeed.
Good luck with the circuit bending!