WIP: Another PI JAMMA Adapter

pcjohn

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Just got the prototype running today. I came up with this for
my own use, but I thought I'd share:

It's a PI-HAT type of design, flip the PI upside down and plug it
into the board. As you see by the pictures, it's pretty damned
small but look what it does:

VGA666 integrated, so it will run on a standard RGB monitor.

Built in joystick controller. 36 digital inputs plus 4 analog inputs
for potentiometers.

Built in Class-D audio amplifier. I need to experiment with this -
it's nice but may not be loud enough for my purposes.

Sadly the GPIO pins don't transfer USB or audio so separate cables
are needed. Most of the GPIO pins are used in the VGA666 and this
was faster than bit banging the data down a couple of the remaining
pins.

You can tell by the jumpers I made a couple mistakes. I'm also thinking of
adding a 5 volt regulator so the thing will run off 12 volts only. Arcade power
supplies are so not-5-volts and I'm not sure what the limits are on the Pi.

Anyway, more to come down the road.

JRD
 

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I added in the 5 volt regulator tonight.

I was reading about Pi's maximum voltages being only 5.25
volts and the more I thought about it the more I felt that there
should be a stable voltage regulator.

I also fixed the various boo boos from the first design. I'll order
the new proto boards Monday and should see the new board
in 2 weeks.

JRD
 
I'm surprised there aren't more entries in the Pi to Jamma game. There are so many options for jamma to PC - Subscribed
 
It's the price point.

We are all cheap people.

Will this be a sub $100 adapter?

Any chance of a failsafe on that 5v line... Say a zener diode?
 
Aiming for below $100. Anyone who knows me (Vectrex)
knows I do this for fun, not profit.

The 5 volt regulator is a 3 amp switching regulator. I use
it in my commercial designs and more than 600 boards
later not one has yet to fail.

The new prototype was ordered Monday so figure a juicy update
in less than 2 weeks. This will give me time to get the BOM together
and source the parts. I worked on the firmware a little today, the
final design will probably have a DIP switch or some kind of option
to tune that damned Mame analog joystick center deadzone.

JD

It's the price point.
We are all cheap people.
Will this be a sub $100 adapter?
Any chance of a failsafe on that 5v line... Say a zener diode?
 

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Awesome design. It would be nice to see something like this for sale at a better price point.
 
Already on proto 3 design. Getting rid of as many through hole parts
as possible. Will help reduce price.

JD
 
...sub $100 shit man you better make more than you think you need

This is going to ffflllyyy out the door
 
Agreed. With the right Pi image, this would be a killer substitute for the 60-in-1 crap out there.

Frizz has that on lock. He cleaned up the ArcadeSD styling for AttractMode.
You can even put that attractmode stuff on the simple RetroPie image which is a fast write to an SD card.

I'm perpetually tinkering with the pi images and attract images people do.
Hands-down the SD theme for Pi is THE best image I've used thus far.
So simple and elegant even little kids have no trouble with it.
 
Frizz has that on lock. He cleaned up the ArcadeSD styling for AttractMode.
You can even put that attractmode stuff on the simple RetroPie image which is a fast write to an SD card.

I'm perpetually tinkering with the pi images and attract images people do.
Hands-down the SD theme for Pi is THE best image I've used thus far.
So simple and elegant even little kids have no trouble with it.

To be clear ... the SDARCADE theme was by a guy named Jedione over at the attract-mode forums (who emulated the ArcadeSD theme)... it ran only on the PC and Dee2er updated it to work with the Pi...

I've tweaked the hell out of it but it's NOT my original code... that would go mostly to Jedione and then Dee2er...

I just wanted to make sure the proper credit be given to the proper folks.

;)
 
It's only vga? No CGA?
Can it be programmed in?

No there is an addon or smth to have cga but this is different.

More of a all in one power supply and gpio mapping solution to the jamma standard.


Which is what I have been waiting for to make a multi thing monster for myself.

But the other solution... Well it looks like shit

It looks like a crab banged a silicone wafer....


This seems a more elegant solution.... But i am hesitant with smd tech...

But for under $100.... It's worth it. Damn good deal in all honesty given what it does and the price point of the alternative
 
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