Arcade

Just another arcade game project -
JAMMA Supergun/MAK Board!
Rev.4 Update!

We love
arcade gaming and self-made arcade cabinets, but honestly - our worst nightmare are those endless JAMMA harness soldering sessions when connecting joysticks, buttons, speaker, display and so on. This calls for some action!

Vision Imagine a rugged and reliable interface for JAMMA-compatible arcade PCBs. The interface should simplify system integration of all electronic components which are usually needed for a do-it-yourself arcade cabinet project. Instead of having to deal with more than 40 individual cables, we would like to connect each component via common plugs and/or sockets thus reducing manual soldering to a minimum. Moreover, common functionality, like color adjustments, test button etc. should already be provided by the interface as well.

Solution Yeah, let's develop a PCB (printed circuit board) which connects to all major components which are usually needed in a self-made arcade cabinet, e.g. power supply, joysticks and buttons for two players, speaker, display and the aracde gameoboard itself, of course.

PCB development requires serious CAD tools and plenty of electronic engineering know-how. Components have to placed accordingly, traces have to be optimized, circuits have to be debugged and so on...
After several weeks of finalizing our design, we have been transferring our CAD files to a PCB factory and finally receive our first boards.
There is still some manual work for us to do, since the factory only delivers the raw PCBs without components. However, soldering components to our PCB is quite relaxing. The final result is rather impressive, let's look at the specs:

JAMMA Connector A 56-pin JAMMA connector is going to connect to any JAMMA-compatible arcade gameboard. We have been using high-quality connectors from the japanese electronics supplier Hirose which are rather expensive but the advantage is obvious: Even unused pins will remain firmly seated in the connector unlike in cheaper versions. The following table provides an overwiev of the JAMMA connector standard. The pins which are supported by our Interface are marked in yellow color. Even the unused pins are available on our interface, making future modifications easy.

Parts Side			Solder Side
GND	1	A	GND
GND	2	B	GND
+5V	3	C	+5V
+5V	4	D	+5V
-5V	5	E	-5V
+12V	6	F	+12V
Key	7	H	Key
Coin Counter 1	8	J	Coin Counter 2
Lock Out Coil 1	9	K	Lock Out Coil 2
Speaker Pos	10	L	Speaker Neg
Audio Pos	11	M	Audio GND
Video Red	12	N	Video Green
Video Blue	13	P	Video Sync
Video GND	14	R	Service Switch
Test Switch	15	S	Tilt Switch
Coin Switch 1	16	T	Coin Switch 2
Player 1 Start	17	U	Player 2 Start
Player 1 Up	18	V	Player 2 Up
Player 1 Down	19	W	Player 2 Down
Player 1 Left	20	X	Player 2 Left 2
Player 1 Right	21	Y	Player 2 Right
Player 1 Button 1	22	Z	Player 2 Button 1
Player 1 Button 2	23	a	Player 2 Button 2
Player 1 Button 3	24	b	Player 2 Button 3
Player 1 Button 4 *	25	c	Player 2 Button 4 *
not used	26	d	not used
GND	27	e	GND
GND	28	f	GND

(*) The buttons 4 for players 1 and 2 are not defined in the JAMMA standard. Nevertheless, we are providing the 4th buttons on our interface anyway since this it will be compatible to SNK's Neo Geo MVS arcade mainboards.

Controller D-Sub 15-pin plugs (male) are wired according to Neo Geo MVS/AES standards We have been using well-known industry standards whenever possible. Therefore, we have been designing both control panel ports (player 1 and 2) according to SNK's Neo Geo MVS/AES standards. Each control port provides a joystick, four action buttons, start and coin-in as well as the 5 volts supply. We have even been remodeling SNK's legendary "double pins 4 and 9" for the 4th button, btw. You can either extend these control ports, plug in any MVS/AES comaptible joystick/-pad or even use a NeoGeo-to-PlayStation adapter. We have been trying out this Tototek adapter with a PlayStation 1 dual shock pad.
If you would rather like to build your own custom control panel with microswitches, you should have a look at our controlpanel PCBs. These allow for easy connection to leaf- or microswitches.

Pin	Name	JAMMA Standard
1	Ground	GND
2	not connected	not connected
3	Select	Coin Switch
4	D Button	Button 4
5	B Button	Button 2
6	Right	Right
7	Down	Down
8	+5V	+5V
9	D Button	Button 4
10	not connected	not connected
11	Start	Start
12	C Button	Button 3
13	A Button	Button 1
14	Left	Left
15	Up	Up

Power Supply A power supply can be connected via 4-pin Molex-type socket. This is a common plug type which has been frequently used in floppy disk drives, CD-ROM drives and so on. Instead of providing a second ground connector, you can connect -5  volts here which may be rarely used by old arcade game boards. All voltage pins are clearly labelled on the interface.

Speaker The JAMMA standard requires to connect an 8-Ohm speaker (mono) here. Since JAMMA-compatible arcade gameboards are supposed to provide an amplified signal with volume control, not much has to be sone here. A standard cinch connector can be used to connect the speaker directly. Do not connect this to an television set or the input of an amplifier! The signal is already amplified and may harm your componet and/or gameboard!

RGB-Video An HD D-Sub 15-pin connector (female) provides 15 kHz RGB-video standard The video output will be provided by a 15-pin HD D-Sub socket. The 15 kHz analogue RGB-signal uses composite synch and can be used with compatible mutisync- or arcade monitors directly. A standard 15-pin VGA cable may be used for ceonnecting the dsiplay but please beware: The video output is still 15kHz RGB video from your JAMMA game boards. Any connected display (multisync, arcade monitor whatever) has to support 15kHz RGB video! Connecting a standard PC-monitor may result in damage to the monitor!

Pin	Name	JAMMA Standard
1	Red	Video Red
2	Green	Video Green
3	Blue	Video Blue
4	Monitor ID2	not connected
5	Ground	not connected
6	Ground (Red)	Video GND
7	Ground (Green)	Video GND
8	Ground (Blue)	Video GND
9	Key (no pin)	not connected
10	Synch Ground	Video GND
11	Monitor ID0	not connected
12	Monitor ID1	not connected
13	Horizontal (Composite-) Synch	Video Sync
14	Vertical Synch	not connected
15	Monitor ID3	not connected

We have also provided trim-pots in case your display needs some input-sensitivity adjustments. Each trim-pot is clearly labelled and will provide individual color sensitivity adjustment (red, green, blue).

Test/Service Buttons Moreover, we have been providing buttons for Test and Service mode on the interface as well. Of course, these will only work if your arcade board does support these functions.
A red LED will indicate if a power supply (5 volts) is connected and active. On some switching power supplies you may see a pulsing LED if no arcade board is connected. This is perfectly okay, since swiching power supplies usually adjust themselves to the load attached.

Conclusion The results are quite amazing - picture quality is superb on our multisync display and the control ports are fully functional without errors.
We are using our JAMMA Supergun/MAK interface whenever we need a hassle-free integration of components into cabinets. For example - we have been using our interfaces in all all of our Arcade Table Workshop creations as well.

Here is the good news for all do-it-yourself arcade cabinet project leaders: We are offering our remaining interface boards on a first-come, first-serve basis for 69,- € each (incl. VAT) (excluding packaging and postal fees, ask for details, please).
All boards are tested and working flawlessly. For questions, please refer to us via email. This is a private sale, so no returns or refunds, sorry.

If you are interested, please contact us via email at ofni.regit-repap@ybbob

Next steps? We have already been designing a set of small (AES/MVS-compatible) control panel PCBs for those who would like to create their own custom control panel and connect to our interface.

All references to the JAMMA standard refer to the JAMMA «First Edition».

Errors and omissions excepted. All descriptions and specifications are subject to change without notice.

Permalink December 8^th, 2008

Arcade Custom PCBs - FAQ
Frequently Asked Questions

Some questions and answers regarding our JAMMA Supergun/MAK Interface PCB:

Does the interface boost the video signal output ("RGB VIDEO") of an attached arcade PCB?

No. This is not necessary since arcade PCBs usually feature a pretty strong video output signal.

What are these adjustment pots (trim-pots) "RED", "GREEN", "BLUE" good for?

You can adjust the video signal output of your aracde game boards to the input sensitivity of your connected display. The center position of the trim-pots is well-suited for most display types. In rare cases, you may want to adjust the sensitivity for each color. Turn the trim-pot clockwise to tone down the signal in case the color are over-saturated. Turn the trim-pot counter-clockwise to increase the signal in case the color is washed out and lacking contrast.

Nothing happens when I am pressing the "SERVICE" button, why?

Not all JAMMA-compatible arcade game boards do support the service button functionality. In fact, very few do. Sometimes, only a credit is added when pressing the service button. This used to help the service technician when servicing the arcade cabinet/game in the field. Please refer to the owner's manual of your arcade game board.

Nothing happens when I am pressing the "TEST" button, why?

Many older arcade game boards from the 80s and 90s do not have a test menu to change settings and options. Most older boards use DIP-switches which are located on the arcade game board itself to change settings. Please refer to the owner's manual of your arcade game board. Some newer arcade gameboards (e.g. some CAVE SH-3 boards) will require you to keep the test button pressed for at least two seconds before the test menu appears.

Can I connect the speaker output ("SPEAKER") to my amplifier or tv set?

No way! The signal is already amplified audio and should only be conencted to a speaker (8 ohms). Connecting the speaker output to other devices may result in damage to the arcade game board and/or the other devices.

Why isn't there any volume control for the speaker output ("SPEAKER")?

Every JAMMA-compatible arcade game board has an on-board audio amplifier with volume control already. Please refer to the owner's manual of your arcade game board for the location of the volume control. On very rare occasions, the audio volume can be adjusted via the game board's test menu.

I have been connecting the control panel PCB with the JAMMA interface (Rev.4) without arcade game board. Why doesn't the status LED light up on the control panel board?

You have to connect an arcade game board to the JAMMA interface (Rev.4) in order to activate the control ports ("PLAYER 1", "PLAYER 2"). Without a connected arcade game board and the proper detection of the JAMMA ground pins (1,2,A,B) and (27,28,e,f) respectively, all connected control panel PCBs remain inactive.

I have been connecting a non-JAMMA arcade game board via a JAMMA adapter to the JAMMA interface (Rev.4). Why doesn't the status LED light up on the control panel board? Why do buttons and joystick remain inactive?

The adapter (cable) for your non-JAMMA game board has not been built according to JAMMA specification. Most likely, the ground connection to the JAMMA pins 27,28,e,f is entirely missing. Please make sure that at least one of the JAMMA pins 27,28,e,f is connected to the arcade game board's ground conectors via the adapter (cable).

The metallic color of some of the vias (holes) has changed on the interface PCB. Why is this happening?

No worries, this is perfectly fine. The interface PCB has been manufactured according to ROHS compliance. Therefore, the metal on the PCB contains high traces of silver which causes the color change effect.

Some questions and answers regarding our control panel Interface PCBs:

I have been connecting the control panel PCB with the JAMMA interface (Rev.4) without arcade game board. Why doesn't the status LED light up on the control panel board?

You have to connect an arcade game board to the JAMMA interface (Rev.4) in order to activate the control ports ("PLAYER 1", "PLAYER 2"). Without a connected arcade game board and the proper detection of the JAMMA ground pins (1,2,A,B) and (27,28,e,f) respectively, all connected control panel PCBs remain inactive.

I have been connecting a non-JAMMA arcade game board via a JAMMA adapter to the JAMMA interface (Rev.4). Why doesn't the status LED light up on the control panel board? Why do buttons and joystick remain inactive?

The adapter (cable) for your non-JAMMA game board has not been built according to JAMMA specification. Most likely, the ground connection to the JAMMA pins 27,28,e,f is entirely missing. Please make sure that at least one of the JAMMA pins 27,28,e,f is connected to the arcade game board's ground conectors via the adapter (cable).

Permalink September 12^th<, 2008