Double Dragon pcb schematics

dyno

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Anyone have or know where to find the schematics for double dragon? I am having issues with player 2 movements and it's not joystick but the pcb.Also anyone out there who has a double dragon pcb, if you could tell me what IC is at the IC110 location in the top right hand corner of the top board that would be greatly appreciated, I am missing that IC. Thanks
 
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Just so happens that I have one sitting on my desk...

The IC at IC110 on mine is labeled 21J-H. You can pull it out of the MAME dumps and reburn.

- Mike
 
dd

i pulled out the 21j-h located at ic110 out of my working board and all it did was have some minor graphic problems on some of the characters
 
I wasn't able to locate one... I ended up spending extra time, but did fix both of the bad boards I had here.

Working on controls is easy. Check the input pins with a logic probe to see if they are tied high or stuck low. They should only go low when the control is activated. If they are stuck low then check for corroded traces at the board connector edge then trace it back to the chips, resistor packs, and other devices on the inputs to see where the signal stops.
 
I wasn't able to locate one... I ended up spending extra time, but did fix both of the bad boards I had here.

Working on controls is easy. Check the input pins with a logic probe to see if they are tied high or stuck low. They should only go low when the control is activated. If they are stuck low then check for corroded traces at the board connector edge then trace it back to the chips, resistor packs, and other devices on the inputs to see where the signal stops.

can i come down and hang out with you for awhile? i wanna learn what all that stuff is that you just said :) i'm not sure if i'm stuck high or tied low, but i'm pretty sure that those connections in my brain need worked on so i can learn and understand all this stuff
 
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