I’m leaving this here for posterity so when the next person who wants to convert Beast Busters: Second Nightmare to JAMMA the info will be searchable. Plus I’ve improved the method.
Here is the pinout to convert everything to JAMMA and to a custom DB15 harness so you can repurpose any old flight stick (non USB) to use. I suggest the Top Gun Thrustmaster but that’s just me.
4 Pin JST VL - Front View
Upper left / Right - 5V
Lower Left/ Right - ground
Note : the official schematic says pin 1 and 4 are ground and 2 and 3 are 5V. My motherboard says differently. 5V are 1/2 and Ground are 3/4.
double check your PCB before you do this step. Maybe there’s a different revisions I’ve never seen but I believe it’s a misprint from SNK...although I’ve warned you now so!
9 Pin JST YL - Front View
1 - sync
6 - video ground
7 - red
8 - green
9 - blue
12 Pin JST YL
1 - ground
5 - test
9 - extra ground
12 - coin 1
note : I only wire up one coin as I set to free play. If you want coin 2 use position 11.
15 Pin JST YL
1 - Stick 1 ground
6 - Stick 2 ground
7 - 2P start
8 - 2P bomb
9 - 2P reload
10 - 2P trigger
12 - 1P start
13 - 1P Bomb
14 - 1P reload
15 - 1P triggee
note : I double up start and bomb for less buttons. So I’ll take pin 7/8 and 13/14 and bridge them in the DB15 connector. The game exhibits zero issues with this method.
13 Pin JST XAP
2 - 5V potentiometer vertical - P2
3 - vertical data - P2
5 - 5V potentiometer horizontal - P2
6 - horizontal data - P2
7 - common ground - P2
8 - 5V potentiometer vertical - P1
9 - vertical data - P1
11 - 5V potentiometer horizontal - P1
12 - horizontal data - P1
13 - common ground - P1
note: common ground chain across pots works fine, as does splitting them up and using pin 1 and pin 4 as additional ground points
12 pin JST XAP
1 - speaker left
2 - Ground
3 - speaker right
4 - ground
note : you can feed these into the JAMMA edge to get down to mono or use them as bare wire leads into some form of sound system. Dealers choice. I left our gun speakers as those sound effects ALSO come through the main audio so...didn’t bother.
4 Pin JST VGR
1 - ground
2 - 12V
3 - 12V
4 - ground
For the sticks I just probe the signal and ground wires for each of the buttons and potentiometer signal needed and map a female DB15 connector to link to the male flight stick pin setup. From there those leads go into the appropriate JST connectors listed above.
don’t common ground the buttons with the pots. Keep them separate. I tried being lazy...the game doesn’t like it. Common ground for buttons is fine AND common ground for pots is fine...but one ground for both is not fine lol
that’s about it. It’s not too hard but it’s certainly a lot of leads. Level of difficulty? I dunno....7/10 on the conversion harness scale?
the ONLY thing you can screw up and cause issues is getting 5V or 12V in the wrong spots. Everything else is really not an issue. Wire a pot up wrong? Just change the lead.
note : don’t expect to get the pins out of the JST VL/YL connectors. I have the tools and even I can’t do it reliably. Buy extras when you order...they are under a dollar and save you a ton of time if you make a mistake.
if you ever need help...I’m always around. This is just my way to get more people to play Beast Busters
edit : Beast Busters: Second Nightmare came with a secondary sound amp. Your audio via mono will be quiet. Just how it is. It’s not bad but you can always bare wire the speaker left and speaker right into amplified speakers so long as they accept bare stereo leads.
Here is the pinout to convert everything to JAMMA and to a custom DB15 harness so you can repurpose any old flight stick (non USB) to use. I suggest the Top Gun Thrustmaster but that’s just me.
4 Pin JST VL - Front View
Upper left / Right - 5V
Lower Left/ Right - ground
Note : the official schematic says pin 1 and 4 are ground and 2 and 3 are 5V. My motherboard says differently. 5V are 1/2 and Ground are 3/4.
double check your PCB before you do this step. Maybe there’s a different revisions I’ve never seen but I believe it’s a misprint from SNK...although I’ve warned you now so!
9 Pin JST YL - Front View
1 - sync
6 - video ground
7 - red
8 - green
9 - blue
12 Pin JST YL
1 - ground
5 - test
9 - extra ground
12 - coin 1
note : I only wire up one coin as I set to free play. If you want coin 2 use position 11.
15 Pin JST YL
1 - Stick 1 ground
6 - Stick 2 ground
7 - 2P start
8 - 2P bomb
9 - 2P reload
10 - 2P trigger
12 - 1P start
13 - 1P Bomb
14 - 1P reload
15 - 1P triggee
note : I double up start and bomb for less buttons. So I’ll take pin 7/8 and 13/14 and bridge them in the DB15 connector. The game exhibits zero issues with this method.
13 Pin JST XAP
2 - 5V potentiometer vertical - P2
3 - vertical data - P2
5 - 5V potentiometer horizontal - P2
6 - horizontal data - P2
7 - common ground - P2
8 - 5V potentiometer vertical - P1
9 - vertical data - P1
11 - 5V potentiometer horizontal - P1
12 - horizontal data - P1
13 - common ground - P1
note: common ground chain across pots works fine, as does splitting them up and using pin 1 and pin 4 as additional ground points
12 pin JST XAP
1 - speaker left
2 - Ground
3 - speaker right
4 - ground
note : you can feed these into the JAMMA edge to get down to mono or use them as bare wire leads into some form of sound system. Dealers choice. I left our gun speakers as those sound effects ALSO come through the main audio so...didn’t bother.
4 Pin JST VGR
1 - ground
2 - 12V
3 - 12V
4 - ground
For the sticks I just probe the signal and ground wires for each of the buttons and potentiometer signal needed and map a female DB15 connector to link to the male flight stick pin setup. From there those leads go into the appropriate JST connectors listed above.
don’t common ground the buttons with the pots. Keep them separate. I tried being lazy...the game doesn’t like it. Common ground for buttons is fine AND common ground for pots is fine...but one ground for both is not fine lol
that’s about it. It’s not too hard but it’s certainly a lot of leads. Level of difficulty? I dunno....7/10 on the conversion harness scale?
the ONLY thing you can screw up and cause issues is getting 5V or 12V in the wrong spots. Everything else is really not an issue. Wire a pot up wrong? Just change the lead.
note : don’t expect to get the pins out of the JST VL/YL connectors. I have the tools and even I can’t do it reliably. Buy extras when you order...they are under a dollar and save you a ton of time if you make a mistake.
if you ever need help...I’m always around. This is just my way to get more people to play Beast Busters
edit : Beast Busters: Second Nightmare came with a secondary sound amp. Your audio via mono will be quiet. Just how it is. It’s not bad but you can always bare wire the speaker left and speaker right into amplified speakers so long as they accept bare stereo leads.
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