Hey I recently purchased a gunforce pcb which runs on the ever popular irem m92 hardware. It runs great however the screen is darker than my other games (weird). Anyway I managed to find information on the dip switch settings for the game but not the jumpers and I was just curious if anyone knows where I can get the information on what the jumpers do.
J1 - Link to allow Jamma connector to output preamp audio. J2 - Selects between 16K / 64K type SRAM chips. J3 - Matches J18 on the ROM board and is to do with the type of Sprite chip the ROM board is using. The others on the otherside of the board are generally to do with what ICs the board is using (as they vary between boards) as well as what type of ROM chips the board is using. As generally jumpers on arcade boards are specific to the game, they are not mentioned as they will generally never be changed...
Mainly by looking at a couple of M92 boards. Generally when jumpers are used on a arcade board they are so hardware that is used between compatable boards can be set up for that specific game and the vast majority of time it is so that certain RAM / ROM combinations can be used. Anything that can be user altered is mentioned in the manual.
