Jamma projects.

shadows

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Currently stuck between contracts, weather is mostly shit and boredom is setting in. So I'd thought I'd finally get around to making my dreamcast, which I only bought for this purpose anyway, jamma compatible.

I still need to add a few things, like a switch to kill the internal controllers, for some light gun action. Also adding video out to the jamma edge, so I can get back my scanlines when in 15khz mode.
It is otherwise done.

Jamma connector, Headphone jack, DB9 kick harness connector and cutout for the memory card.
DCJamma_01.jpg


VGA connector, 15/31khz switch.
DCJamma_02.jpg


Guts spilled open.
There's two internal controllers with one slot for a memory card.
All of the components that sit on the top metal panel are going to connectors, strip boards. Making everything very easy to take apart when needed.
DCJamma_03.jpg


And a look inside the gutted modem shell.
DCJamma_04.jpg


Next up, is a Genesis. This one is going to be a much quicker project to do.
Using an harness going to the Sega CD extension port, instead of adding a jamma connector to the shell.
 

mr_b

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Awesome work man. Thats some clean work. I wish my projects could be that clean and tight.
 

opt2not

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Nice use of the internal space! Very cool.
 

shadows

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Thanks.
The Genesis is going to be a different kind of clean.It's an ugly bare board to look at. But now that fully killed the shell after dropping it yesterday, which was already damaged. I dont have much choice.
Oh well.
 

jeffkun34

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Holy Shit is that some clean work! Bravo!
 

shadows

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Finally got around to finishing off the Genesis.
Ended up finding a non working Genesis locally for next to nothing, so I could use the shell.
Not much to look at.

On-Off switch is used for region selecting between JP and US. I could have used the original switch, but I only thought about it after I had already cut off the shaft and milled out the power button. Oh well.
Reset is hooked up to the service button of the cab.
Cut all the traces going to the edge connector, so I could run everything from the edge to a jamma adapter.

GENJamme_01.jpg

GENJamme_02.jpg


Eventually I plan to put a second set of controllers in there, for 3 buttons games for a better button layout. With some switches to fill up the now empty controller port holes.
 

Lemony Vengeance

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hate to bump a year old thread, but have tutorials ever come out for these? I know MrB did one for the genny, but this DC mod is amazing!
 

shadows

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codecrank is making himself one and I think he is going to post an how to when he is done.
 

Lemony Vengeance

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did you make the VGA mod Modular by wiring it to the modem connector, then custom wiring the video to the connector inside the DC?

Because if you did, that's genious.

Also, will this allow you to switch between RGB over Jamma and VGA?
 

shadows

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Yea its reusing the modem connector since I had no use for it anymore. Kept things cleaner.

At the moment its only wired for video over VGA with a switch for 15/31khz.
 

Lemony Vengeance

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would it be possible to make it switchable between VGA and Jamma? I don't know if you can tell, but I'm INCREDIBLY interrested in doing this.

One more question.. Why go with a female jamma connector rather than the male?
 

shadows

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Yea you just need a switch to ground the right video select pin.

I did it that way mainly to make a stronger and more stable connector.Since I wasnt sure if just having some long screws holding the fingerboard in would have been good enough.
 

Lemony Vengeance

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so using a female connector and using something like this to make it possible for another female to connect:

http://www.jammaboards.com/store/classic-jamma-fingerboard-stick-fb-1.html

would work, right? I'm trying to wrap my head around this.

By the time I'm done, I ultimately want to mod the bios to run Dreamshell and add an SD reader to it to eliminate the need for the GD-ROM.

also, how did you get power running over jamma?
 
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shadows

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Yea that would work, youd just have to cut the end of it.

Used 5 and 12v over jamma and used a dc dc converter for 3.3v. If youre going to only use it in your Blast City, you could use the 3.3v rail from the psu instead.
 
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Lemony Vengeance

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Yea that would work, youd just have to cut the end of it.

Used 5 and 12v over jamma and used a dc dc converter for 3.3v. If youre going to only use it in your Blast City, you could use the 3.3v rail from the psu instead.

I want to make it plug and play for any cab so I'll need to go that route too. any hints on how you got it working or should I wait for CodeCrank's tutorial?
 

shadows

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Youre going to need a dc dc converter that can handle 3amps. I dont have my notes anymore so I dont remember the exact figure but it was below 3amps, 2amps something.
All the other info needed for the converter is going to be in the schematics. Very straight forward.
 
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