What's new
my version 1.2c build. Not bad for an smd rookie!

dsYsOTV.jpg
 
Hi @Frank_fjs, seems difficult to make a fork of the Minigun with only the JSON file and without the schematic? Is there another way to approach this? EasyEDA noob here.
 
Start fresh?

All the nets are labelled, shouldn't be too hard to follow. Click the design manager tab and look at the net folder.
 
I'll give it a shot. Will start small and just replace the DB15 connectors with momentary tactile switches for player inputs. Test bench version (hopefully).
 
Ahh crap. One small little error I need to resolve, will do a 1.6V in a day or so. Then I can call it finalised.

Mixed up the left and right audio channels in stereo mode, so the right channel plays through left speaker and vice versa. Not a major issue but one that needs to be rectified.
 
does that affect the older ones too?

Other questions.

Kick harness: how do we ground the kick harness? There's only 6 pins, which I imagine are for the buttons. Is this an oversight or was it designed to have the ground be external from the connector and just grounded to a ground jamma pin?

What is the pinout for the kick harness? I'm sure I can figure it out, but it would be nice to make it official, I suppose

I havent been able to test the board yet cuz I still gotta make the cables and waiting for neo geo converters.

Lastly, I was just curious, how long does it take you to completely assemble your board? It took me 2 hours. Not surevm if that was fast or slow
 
Last edited:
Is it just me or should the writing be flipped to face upright when the board is plugged in so as to be able to read it right side up?
 
does that affect the older ones too?

Other questions.

Kick harness: how do we ground the kick harness? There's only 6 pins, which I imagine are for the buttons. Is this an oversight or was it designed to have the ground be external from the connector and just grounded to a ground jamma pin?

What is the pinout for the kick harness? I'm sure I can figure it out, but it would be nice to make it official, I suppose

I havent been able to test the board yet cuz I still gotta make the cables and waiting for neo geo converters.

Lastly, I was just curious, how long does it take you to completely assemble your board? It took me 2 hours. Not surevm if that was fast or slow
As far as ground goes for the kick harness i'm not sure (I'm still learning about this), but I found the pinout for the kick harness online at https://wiki.arcadeotaku.com/w/Kick_Harness for the CPS2 end of things
Also, at least on my PCB, the bottom has the silkscreen for the button mapping. Two hours seems fine, my first one took me a while too.

aVFK9kr.jpg
 
oh crap, I hadn't noticed that on the back! Thanks for the headsup!
 
It looks great. I'm waiting for 1.5 Advanced pcbs but it's really nice to see new improvements and tweaks in this project.

Have you considered joining both +5V traces from the power supply connector? that's a minor modification that would reduce the possible voltage drop for larger boards.
 
No need for ground with the kick harness connector, the PCB is grounded from the power supply. You need only connect the signals for buttons 4,5,6 etc.
 
ok cool. Thanks frank.


About the stereo mixup, does that only affect 1.5, or all versions?
 
It will affect all versions sadly. :(

It's not such an issue, audio still works as intended, just with the channels swapped around 8o
 
One possible workaround, use a 3.5mm to twin RCA cable, then you could simply swap the red / white RCA jacks around.
 
I have just assembled this Minigun 1.1 Advanced. The PCB comes from JLCPCB, it fits perfectly with the KEL connector. This unit will be used with speakers so I've not soldered the audio parts. I'll connect audio to ground under the minidin connector. This minidin 8 connector feels way better than the chinese connectors I linked before, so I recommend sticking to the ones recommended by Frank.

I've bought a EDAC key and it works fine, but the hirose feels more solid and it sticks in place way better. Both do the trick, though.

The voltage drop is only 0.01V from the molex connector to the jamma pins for a large board with tons of ttl chips I have tested. With this large board, voltage drop is 0.1V from the PSU to the molex connectors, I think the culprit is the wire. Update: I've used thicker wire and now voltage drop is only 0.03V for another big board.

minigun-11-kel.jpg
 
Last edited:
That looks great @rsignal

I also have the cheaper Chinese DIN connector and noticed the higher quality of the digikey stuff. The difference in weight is the first thing that stands out.

Sullins edge connector is superb.

What are your thoughts on the Molex power connector on the advanced? Should I keep it as is or switch it back to the ATX style the standard uses? After trying both, I'm kind of liking the ATX style better.
 
I've only tested the one in the photo from my previous post (Molex 35318-0620) so I can't compare. This one works for me, will test the other and report back when the 1.5 advanced pcbs arrive.

I'll get some Sullins jamma connectors in my next order if they are available, thanks for the suggestion.

Update: Finally I reduced the voltage drop using 6x 7 inches 18AWG cables. 16 AWG cables are too thick for these Molex connectors, these ones work fine if you keep them short enough.
 
Last edited:
Revision 1.6 up.

Main note of interest is correcting the left / right audio channels being reversed in the advanced PCB when stereo audio output is utilised.

I believe this wraps it up for me. It's a refined error free product now. Enjoy.
 
Back
Top