Main > Main Forum
OpenJamma board - interest?
<< < (28/43) > >>
launton:
Exactly what I'm after.  Bring it on!  :applaud:  :cheers:
sandheaver:
I still think you'd be better starting from an already open platform like the new BeagleBone Black.  It has a lot of the same specs as what you're aiming for, and it's already made, prototyped, tested, and released.

You could more easily create a cape (what the beagleboard people call an add-on card) that has most or all of the interfaces you want on the openJAMMA board, and the main board with CPU & GPU is already done for you, and for far less money than it would cost you to design, prototype, and build it.

Given the $45 price tag for this, you could sell a cape that sat on top and still meet your $100 goal for the solution, in total.

Also, there are already VGA capes for this guy, so there's one less thing for you to worry about.

Maybe you're too far in to change direction now, but I would encourage any future embedded JAMMA designers reading this to consider this type of a solution (an IO board for an existing platform) in the future.  It's much less work, much less risk, much less cost, and much more easily supported.

The CubieBoard is similar and even has SATA, if you really need that.

My $0.02.
sharpfork:
I agree about the beaglebone black or cubie and capes.  Make one for CGA Jamma, a different one for VGA jamma, and a different one for VGA with wire terminals.

I've been pondering  something like that as a KADE project but the hardware with decent I/O is not quite fast enough to emulate n64 and ps1 well.  The fast boards like the odroid don't have enough I/O.  Playing with the Ouya might tide me over if a big community grows around it and I can get my HDMI to VGA converter working.  I'll pick up an openjamma board too.


SIII + Cyanogen + Tapatalk 2

sandheaver:

--- Quote from: sharpfork on May 03, 2013, 06:32:34 pm ---The fast boards like the odroid don't have enough I/O.
--- End quote ---

the ODROID-X2, even?  I thought it had 50 pins of I/O..  I could be wrong, I read that page a long time ago, and I'm not going to re-read it now, just to deny someone the opportunity to tell me I'm wrong.  People seem to enjoy that, and who am I to rob someone of their joy?   ;D

The ODROID-X2 has enough I/O.  You could make an add-on card for this board and do what you wanted.  This platform is nice because it has a quad-core CPU.  Clever software authoring could use a whole core for MAME and nothing else.  I don't believe MAME supports multiple cores yet, does it?

You only need a few I/O pins if you use them to drive an extender or something like that.  use an I2C bus to drive an I/O extender and handle the I/O from there.  Arcade monitors need a 5V signal (if we're being strictly pure to spec; late model CRTs handle 1v just fine) so you'll need an amplifier or you'll need to require a video amp be used as a separate component if needed.  Not sure what voltage the speaker would need to be.

Trick would be to get video onto the I2C bus in the first place.  Software rendering could do that easily enough, I suppose.

It could be done, and while I2C might not be the bus of choice, making expansion boards would be a whole lot easier than building the entire thing, base platform and all, from scratch.
sharpfork:

--- Quote from: sandheaver on May 03, 2013, 07:02:53 pm ---the ODROID-X2, even?

--- End quote ---

It's $135.00 + shipping, different class of product.  The BeagleBone Black and Cubie are ~ $50.
Navigation
Message Index
Next page
Previous page

Go to full version