JPAC + Input Button 4

[DaveJ-UK]

I have the first 4 buttons wired directly to the JAMMA harness and buttons 5 and 6 connected to my JPAC's P1B5 and P1B6.

However I notice that it also has a P1B4 screw connection - why does it have this if it goes directly through the JAMMA harness anyway?

It's definitely meant for button 4 because it generates the same keystroke (left shift)? Is it just there for convenience if you have a 3 button cab and dont want to wire the exrtra button to the harness?

[nobbo]

i believe the official jamma standard was 3 buttons, although some machines extended this to 4 buttons, and of course the capcoms of the world invented jamma+ which is 6 buttons per player, so most jamma cabinets will only have 3 buttons wired, but some (like yours) use 4 buttons directly into the harness.

there is no difference whether you use the screw terminal on the j-pac or the harness though

[CheffoJeffo]

As nobbo says, JAMMA standard is 3-buttons, although some cabinets will wire button 4 to pins c and 25.

From the JPAC FAQ:

Note that button 4 can be connected via either method as some JAMMA harnesses route this button through the connector.

Cheers.