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I own a jvs-pac and i'm also curious about this since i know you put out great products. Any idea about price range?
Good luck with the project.
 
I'm pretty happy with the proto-type, so if nothing pops up the production should start shortly. A big unknown at the moment is sourcing the main IC on this thing, as it seems to be affected by the global IC shortage. I think an optimistic estimate is 8 weeks if all components are sourceable. Pricing is TBD as I haven't received a quote for manufacture yet, but hopefully it will be in the same ballpark as the Jammafier.
 

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Question for you guys, is a push type DC connector like this OK? It's not a beauty, but makes my life a lot easier..
 

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Another question, any interest in sdram modules? It's not the "official", different caps and power, and a more "traditional" (i.e. non-crazy) layout - no vias/holes in the SMD pads, and dedicated ground and power layers in the PCB. I did this mostly for fun as I need more the >32mb I have now. The against column is that the margin is low - you can get modules for 47USD+shipping from China - there is no way I can compete with that, and I don't want to get stuck with expensive inventory.

I could potentially do an exclusive, i.e. only possible to get as a bundle with the Jammafier. I have no idea if people interested in the Jamma expander already have a working MiSTer setup..
 

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Since the memory question came up, have you seen this project from aje_fr: https://www.neo-arcadia.com/forum/viewtopic.php?f=14&t=74689
It appears to incorporate 128MB on the interface board directly, not a separate module.
The only thing I think is missing on his version are outputs for unamplified audio.
The MISTer stuff is a bit of a moving target, and although it wasn't the primar reason - keeping the GPIO pins available is IMHO a good thing.

aje_fr makes some cool thingies for sure, actually buying them otoh is not trivial from what I understand
 
I think you should avoid manufacturing and selling SDRAM modules - their design is a moving target as the latest CPS1.5 and CPS2 cores reveal timing issues with the older PCB layouts. There's a very high risk of you getting stuck with unsold inventory.

As for the push-type DC connector, it would be nicer if power was supplied through the hat pins like the other JAMMA solutions out there IMHO, but it's not a deal-breaker either. It's unobtrusive and functional.
 
I think you should avoid manufacturing and selling SDRAM modules - their design is a moving target as the latest CPS1.5 and CPS2 cores reveal timing issues with the older PCB layouts. There's a very high risk of you getting stuck with unsold inventory.

As for the push-type DC connector, it would be nicer if power was supplied through the hat pins like the other JAMMA solutions out there IMHO, but it's not a deal-breaker either. It's unobtrusive and functional.
It will be super interesting for me to see how my SDRAM module actually performs with memtest, scope probing etc. Should be getting the prototype PCB next week, and I hope the weird pin connector from china shows up in the mail soon.

When powering via the GPIO pins, you're bypassing this clever protection circuit on the DE10 and going straight to VCC5, which quite a few components on the DE10 is using directly. Should something mess up VCC5, you can cause a great deal of damage. When factoring in 'common arcade expert knowledge' like raising JAMMA 5V to 5.1 or 5.2, using inadequate power wires in cabs and some of the support emails I've gotten on the Jammafier, this seems just too risky an option for me :)

1620336709447.png
 
SDRAM module performed marginally better than official, 143MHz ran without errors for hours. Probed a bit, and the challenge is the address signals coming from the DE10 - i.e. this will most likely not be something I'm going to sell.


sdram 2.jpgsdram 1.jpg

Received a box with custom length USB and HDMI cables today, and this is what will ship with the Expander. I have also received two trays of the CPU's for this board, so everything should be pretty much ready for production. Excuse the dirty proto, the assembled one will be blue and shiny 8)

There will be no pre-orders (or collecting of money) in advance, but maybe I should do an 'interest list' where people on the list will be given 24hrs or so to order before it's public?

There will be 100 boards in the first run, which is about as much as I'm willing to risk on a new design.

2021-05-19 jamma expander.jpeg
 
Please add me to the list already 😅

edit: probably stupid question of me but the cable connected right over the jamma edge doesn’t cause any issues on cabs with thicker jamma connectors? Or standard ones for that?
 
edit: probably stupid question of me but the cable connected right over the jamma edge doesn’t cause any issues on cabs with thicker jamma connectors? Or standard ones for that?
Clearance is more than adequate, I'll try to snap some pics illustrating it before release.
 
Ok, so Im going to need one of these, awesome work. Love the layout, board size. Definitely put one aside for me when you are ready to sell these.
 
Clearance is more than adequate, I'll try to snap some pics illustrating it before release.
Yeah I assumed you had already thought of it, but thanks for taking your time snapping some pics :) Again please add me to the list hehe
 
interested as well, one to start but prob one or two more down the road
 
Ah, there is no way I can keep track of forum lists :P Not entirely sure it's a good idea, there will be a a list :)

People on the list will be given notice in advance, and possibly a private purchase link. There is no obligation to buy if you're on the list, and I will not spam.

https://irkenlabs.com/about/contact
 
I messaged you on your contacts as you link, and saying it here too in for 1 please 😁
 
Hello im new to the mister,

quick question im looking to buy a mister and i want to use it with the jamma board your doing on a vewlix.

what do i need to buy on the mister side
The main board ofcourse but should i buy the usb board that go on the bottom or the standard i/o board or the digital i/o board?

should i just buy a complete mister?
 
Hello im new to the mister,

quick question im looking to buy a mister and i want to use it with the jamma board your doing on a vewlix.

what do i need to buy on the mister side
The main board ofcourse but should i buy the usb board that go on the bottom or the standard i/o board or the digital i/o board?

should i just buy a complete mister?
Just the main board, and the memory module on top of the product in the thread I believe
 
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