Minigun Supergun - An Open Source Supergun

[xodaraP]

The CPS2 should be fixable. If it was 12v through the +5 or -5 it would be a different story.

As above you have most likely blown one or more polarised caps, these are used for power line filtering and are easily found

If you were in Australia I’d take a look at it for you, there should be someone near you who can help though

Please disconnect your CPS2 until you are 100% sure your voltages are good and everything is connected correctly

 

[GeorgeSpinner]

@Moebius you should post a picture of the fully wired power supply, before you try to use it again, so that you can get assurance it won't cause you any more trouble.

It's probably best to wire up all the connections and not just the +5v.

I believe you aren't going to get sound without the +12v connected. -5v is not needed for CPS2 but can't hurt to have it connected.

 

[Moebius]

Please post more pics of that power supply and power cable (both the AC cable and the DC to minigun cable) I cant really see that clearly from the pics, but maybe I think you've got...
-5v on the DC side of the power supply connected to +5v on the supergun?
and
Earth on the AC side of the power supply connected to GND on the DC side of the supergun???

So the -5 thing is not the end of the world. DC kind of doesnt care which way it goes (and in fact for decades we thought it flowed the wrong way).
Depending on which model of minigun you have it's likley there are no polarised components - so there is a good chance there is no damage there
The CPS2 A board DOES have polarised components on it. Those are little caps are polarised and they DO care which way the current goes (they cared enough to blow up in this case). But everything else on the A board has a reasonable shot of surviving this unharmed.

Do you have a multimeter and the ability to measure DC current with it? if so we could perfom the following troubleshooting steps in reasonable safety


1) wire up that power supply correctly
1a) start with getting AC live, neutral and earth wired correctly (typically Black goes to hot/live, white to neutral and green to earth)
1b) on the DC side there are no real color standards, But this cable looks particuarly non-standard. From the photo it looks like it could be as follows
Black = COM (pretty sure about this)
Yellow = -5 (this is weird)
Blue = +12v (this is also weird)
Red = +5v
2) test the voltages on on that 6 pin connector BEFORE connecting it to the minigun
3) connect the power to the minigun and then test the voltages on the JAMMA edge
4) connect the minigun to the CPS2 A board and test the voltages on the JAMMA edge
5) replace that cap and see if it lives

Below are some pictures of both cords and the PSU, if you need clearer picture of any specific part of either please let me know. I did not have a multimeter prior to the first test but went out and got one today. Probably won't be able to test it today but when possible I plan to attempt it again once properly set up based on your instructions.

Sorry to hear about your A board

I feel fortunate that the A board suffered as little damage as it did honestly. Thankfully it seems like replacing the cap isn't too huge of an issue and I just need to look into what exact piece I need. The shell was inside the board, cracked in half, so identifying it shouldn't be too hard.

@Moebius you should post a picture of the fully wired power supply, before you try to use it again, so that you can get assurance it won't cause you any more trouble.

It's probably best to wire up all the connections and not just the +5v.

I believe you aren't going to get sound without the +12v connected. -5v is not needed for CPS2 but can't hurt to have it connected.

In the instructions that had come with it says that "The minigun only requires the +5v to be connected to operate, and the other voltages just pass to the JAMMA connector". I had interpreted this as meaning only the +5v being needed to be connected for the full setup, when I'm guessing this meant solely the minigun.

 

[hatmoose]

OK - lets do the AC (Mains power) to the power supply first.
It looks like you are in a 110v location (USA) and the power supply is already set to 110v - nice.
Being mains voltage these are quite dangerous - 110v is less likely to kill you than 240v where I live, but even 9v in the right place can stop your heart. Also where I live there is no legislation to sue for personal harm. You are taking advice from internet strangers at your own risk.

I'm sure I dont have to tell you to do this with the mains cable switched off an unpluged, but just in case... Make sure the mains cable is unplugged and switched off

This is your AC cable


The black, white, green tails go into the power supply like this - Green goes to that thing with the lines (Earth), White goes to AC/N (Neutral) Black goes to AC/L (Live).


That should be the AC side "done". The terminal block on that power is now connected to live mains. Any time it is plugged in and switched on it has the potential to cause serious harm.

 

[hatmoose]

Now we can do the DC side, the minigun power cable.

As far as I can tell all revisions of the Minigun have the same power pinout - I only checked back as far as 1.7 and i'm not sure what version yours is, so It would be great if someone could confirm this

Actually the creater of the minigun (FrankFJS) has confirmed the pinout here so I think we are pretty good to go
https://www.arcade-projects.com/threads/minigun-supergun-an-open-source-supergun.9408/page-37

As I said before - there are NO COLOR standards of arcade power supplies, lots of conflicting psudeo standards, but nothing set in stone.

NORMALLY the soft standard is as follows - yours is NOT this
Blue = -5v
Yellow = +12v
Red = +5v

Based on the picture you posted it looks like your cable is actually this - it looks like what might of happened is that they crossed over the blue and yellow wires when they were making it? As I said, there is no established standard for this, so that's not wrong, but it sure is confusing.
Blue - +12v
Yellow = -5v
Red = +5v

So that being the case you'll be wiring this cable to the DC side of the power supply


With these pins - this feels weird and un-natural to me - but it's what I see. Hopefully someone else can confirm. Red goes to +5v 15A. Black goes to COM (doesnt matter which one), Blue goes to +12v 4A, Yellow goes to -5v 1A.
This will only work for the specific cable you have pictured and only because it is (in my opinion) wired up wrong


Ao at that point the AC side will be connected correctly, the DC side will be wired correctly for your specific cable, and we will be ready to probe those pins to make sure we are getting +5v, +12v and -5v where the minigun is expecting to get it

If others could please confirm, expecially about the blue/yellow wires on that cable being swapped over, that would be great

 

[nem]

If others could please confirm, expecially about the blue/yellow wires on that cable being swapped over, that would be great

How you have it in your post is correct. For the cable @Moebius has, blue is +12V, yellow -5V.

 

[GeorgeSpinner]

the instructions that had come with it says that "The minigun only requires the +5v to be connected to operate, and the other voltages just pass to the JAMMA connector". I had interpreted this as meaning only the +5v being needed to be connected for the full setup, when I'm guessing this meant solely the minigun.

I had the same instructions in my first minigun Supergun (maybe we purchased from the same guy) and they also confused me.

You can probably find my posts asking about that topic and the supergun assembler's response in this thread if you wanted.

The supergun only needs +5v but the PCB may have other requirements, so they are passed to it.

I am running an MVS with only +5v supplied to the minigun because I don't need the sound amp powered with the +12v (with the stereo mod, the sound is tapped before it reaches the amp).

 

[saucydaddy]

I'm wondering how people are still making these since a few of the digikey components are sold out and the lead time is pretty crazy for some of them.

https://www.digikey.com/en/products/detail/jst-sales-america-inc/B6B-XH-A-LF-SN/1000381
https://www.digikey.com/en/products/detail/bourns-inc/3362P-1-102LF/1088411
https://www.digikey.com/en/products/detail/panasonic-electronic-components/ERJ-8ENF1001V/86206
https://www.digikey.com/en/products/detail/panasonic-electronic-components/ERJ-8ENF8200V/1746098

Is it ok to swap these for the direct substitution components? or just buying some of these off ebay? Do you guys have any suggestions for brand substitutions on the digikey?

Thanks

 

[buffi]

Is it ok to swap these for the direct substitution components?

Yeah, just swap for something with similar specs

 

[TodoRojo]

Hey everyone,

I'm here to help continue to beat this dead horse.

I have a Framemeister that I'm planning to use. Going through this thread and through some articles on retrorgb.com, here's what I'd like someone to check my knowledge on (some of these options are hypothetical and not the most efficient because I'm trying to wrap my head around TTL voltages and sync):

• Minigun 2.5 Advanced and use a cable like this one: Minigun → 8pin to 8pin → Framemeister → HDMI (add the booster in conjunction with F3)
• Minigun 2.5 Advanced and use this cable: Minigun → 8 pin to scart → scart to 8 pin → Framemeister → HDMI (this should not need a 470 ohm resistor on sync as the sync is not TTL)
• Minigun 2.5 Advanced 9 Pin version with this cable here (470 ohm resistor on sync) with TTL enabled: Minigun → 9 pin to scart → scart to 8pin → framemeister → HDMI

If all of those options are correct, that means I kind of understand that TTL requires a 470 Ohm resistor to bring the voltage down on sync in order to not blow up SCART equipment. The Minigun does not natively output TTL, though, so the resistor is only required if using the 9 pin version with TTL enabled. Furthermore, the Axunworks Supergun would require a 470 ohm resistor on SCART because it's TTL.

Last thought: if one were using TTL for sync (let's say in the Axunworks) and used a dsub (VGA) to 8pin (into the Framemeister), would that require a resistor on sync? Or is that a no due to having sync carried through H-sync and V-sync?


Sorry for the word vomit and tangent.

 

[hatmoose]

So many ideas in here.

Basic principal is
Minigun 2.5 8 pin
RGB = 75ohm Only
Sync = 75ohm only
So for this you are going to want “straight through” cables with no resistors/caps in them

Minigun 2.5 9 pin
RGB = TTL only
Sync = TTL or 75ohm (via jumper)
So for this you are going to want “normal” cables that have resistors/caps on the RGB lines, and to set the sync jumper to 75ohm
Even the crappiest 9pin scares cables are built to the Megadrive2 pinout and have the resistors/caps on the RGB lines.

There are not a lot of use cases for TTL sync. About the only one I can personally find is using the 129x clone card in my PVM9L2. The OSD sometimes flickers on 75ohm sync, moving to TTL sync fixes that.

Anyhoo - to go through yout use cases

• Minigun 2.5 Advanced and use a cable like this one: Minigun → 8pin to 8pin → Framemeister → HDMI (add the booster in conjunction with F3)

Yes

• Minigun 2.5 Advanced and use this cable: Minigun → 8 pin to scart → scart to 8 pin → Framemeister → HDMI (this should not need a 470 ohm resistor on sync as the sync is not TTL)

Yes

• Minigun 2.5 Advanced 9 Pin version with this cable here (470 ohm resistor on sync) with TTL enabled: Minigun → 9 pin to scart → scart to 8pin → framemeister → HDMI

I dont think that will work because the plug on the cable (genesis 1 standard is full-size DIN) will not physically match the socket on Minigun advanced 9 pin (which is mini-din)
Instead have a look at the same cable but genesis 2 standard (Mini-din 9) like this one - this is a particuarly expensive one - even the cheapest MD2/Genesis2 cables off aliexpress work too
https://retro-access.com/collection...-rgb-scart-cable-composite-video-sync-version

 

[TodoRojo]

So many ideas in here.

Basic principal is
Minigun 2.5 8 pin
RGB = 75ohm Only
Sync = 75ohm only
So for this you are going to want “straight through” cables with no resistors/caps in them

Minigun 2.5 9 pin
RGB = TTL only
Sync = TTL or 75ohm (via jumper)
So for this you are going to want “normal” cables that have resistors/caps on the RGB lines, and to set the sync jumper to 75ohm
Even the crappiest 9pin scares cables are built to the Megadrive2 pinout and have the resistors/caps on the RGB lines.

There are not a lot of use cases for TTL sync. About the only one I can personally find is using the 129x clone card in my PVM9L2. The OSD sometimes flickers on 75ohm sync, moving to TTL sync fixes that.

Anyhoo - to go through yout use cases

Yes

Yes

I dont think that will work because the plug on the cable (genesis 1 standard is full-size DIN) will not physically match the socket on Minigun advanced 9 pin (which is mini-din)
Instead have a look at the same cable but genesis 2 standard (Mini-din 9) like this one - this is a particuarly expensive one - even the cheapest MD2/Genesis2 cables off aliexpress work too
https://retro-access.com/collection...-rgb-scart-cable-composite-video-sync-version

Definitely apologize for having the wall of text but thank you for entertaining my thoughts here. I’m definitely a rubber-duck debugging type person.

I wasn’t aware the 9pin on the mini was not the same as the sega; thank you for pointing that out.

I believe I’m starting to understand, on the surface, how these video signals work. Again, thanks for confirming those and spending the time to answer.

 

[Lenzz]

Hi

sorry about this but i have just purchased one of these from eBay already constructed. its the 8 pin mini din version. I was wondering were i can buy a compatible scart cable that is already constructed for my PAL tv . i see they have them on retro gaming cables but they seem fairly expensive . Ive got an MVS with metal slug 2 and KOF 97 gathering dust on a shelf and have decided its time to actually fire it up. I've never used any arcade hardware so haven't got a clue what i am doing

 

[the Goat]

I was wondering were i can buy a compatible scart cable ... i see they have them on retro gaming cables

You've got it.

 

[xodaraP]

You can buy them from RGC or you can get the 8 pin to SCART adapter from etim (you will need to build this yourself) and it comes with an 8 pin cable you can replace if required.

 

[Lenzz]

You can buy them from RGC or you can get the 8 pin to SCART adapter from etim (you will need to build this yourself) and it comes with an 8 pin cable you can replace if required.

thanks for the info , think im just gona bite the bullet and build my own scart cable , got some 8 pin mini din connectors coming in the post and was gonna cut up an an old VGA cable for the cable.

I believe the below image shows the correct pins for the scart . Im still in the research stage as dont want to blow anything up, ill be hooking it directly to my pal crt tv.

on the subject of blowing things up , I have yet to purchase a power supply for my minigun , the only thing i will be using it for is a mvs "MV1B1". is there any way i can forgo an arcade PSU and just hook it to a standard 5v power supply that plugs directly into the wall.

 

[GeorgeSpinner]

thanks for the info , think im just gona bite the bullet and build my own scart cable , got some 8 pin mini din connectors coming in the post and was gonna cut up an an old VGA cable for the cable.

I believe the below image shows the correct pins for the scart . Im still in the research stage as dont want to blow anything up, ill be hooking it directly to my pal crt tv.

on the subject of blowing things up , I have yet to purchase a power supply for my minigun , the only thing i will be using it for is a mvs "MV1B1". is there any way i can forgo an arcade PSU and just hook it to a standard 5v power supply that plugs directly into the wall.

On my mv1c I am using a raspberry pi power supply. I adapted a USB cable to the 6 pin connector. I am only using +5v (since that's all I've got).

With the above setup a stock mv1c would have no sound. 12v drives the amp. With the stereo mod, the sound is tapped before the amp. I have performed the stereo mod.

I'm guessing something similar would be required for your board.

You can also look into power supply bricks that have +5v and 12v.

Something like this:

https://www.digikey.com/en/products...Q2jsTGkrjQ6FS6tcSNryIp8tPS4J8ij4aAk32EALw_wcB

You would have to adapt the din to the proper connector.

I am not saying that adapter is sufficient, I'm just saying it's a starting point.

 

[xodaraP]

thanks for the info , think im just gona bite the bullet and build my own scart cable , got some 8 pin mini din connectors coming in the post and was gonna cut up an an old VGA cable for the cable.

I believe the below image shows the correct pins for the scart . Im still in the research stage as dont want to blow anything up, ill be hooking it directly to my pal crt tv.

on the subject of blowing things up , I have yet to purchase a power supply for my minigun , the only thing i will be using it for is a mvs "MV1B1". is there any way i can forgo an arcade PSU and just hook it to a standard 5v power supply that plugs directly into the wall.

Yes, consolizing MVS boards is common and relatively easy. You can 5V mod the board and they run off approximately 2-3A

Most people use a laptop charger, I modded a 2 slot to run on USB-C and can run it off a phone charger or power bank

If you’re going to go the route of modifying it for power, I recommend also tapping video and audio straight from the board. That way you can use whichever connector you want and don’t need to worry about the 8 pin cable.

 

[obitus1990]

Anyone using the Sync Cleaner sub board with this? I am using the 680K Ohm resistor per the BOM, but, nothing will sync on my OSSC when I try it. The datasheet for the EL1883 states that a 681 KOhm 1% resistor should be used in order to get proper NTSC timing. Is the 680K that Frank has listed in his BOM generating PAL timings instead, and possibly giving me my NO SYNC issue on the OSSC? I have adjusted the porch settings as recommended when using this sync cleaner in the first page of the thread.

 

[hatmoose]

Anyone using the Sync Cleaner sub board with this? I am using the 680K Ohm resistor per the BOM, but, nothing will sync on my OSSC when I try it. The datasheet for the EL1883 states that a 681 KOhm 1% resistor should be used in order to get proper NTSC timing. Is the 680K that Frank has listed in his BOM generating PAL timings instead, and possibly giving me my NO SYNC issue on the OSSC? I have adjusted the porch settings as recommended when using this sync cleaner in the first page of the thread.

Words on a message board are an imperfect medium. I’m not being rude or disrespectful, and definitely not flexing on ya. Just checking we have a common understanding.

The MiniGun supergun is RGBS only. It does not do any video encoding and doesn’t produce composite video, so no PAL or NTSC.

The board on page 1 is a sync booster, it’s designed for the 8-pin version to generate TTL sync. This is desirable in a couple of very specific edge cases
1) using the VGA input on the OSSC
2) some weird arcade boards that produce not-quite-standard sync

If you can share more detail about your video chain we can probably troubleshoot pretty quickly. But I suspect it’s going to be because your Minigun wants to send RGBS and your OSSC is looking for sync on composite.