Talk:Vs. System
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Is there a way to detect if the game is running on Vs. System or not (which also works in emulators)? In case I wanted to make up the game which can work coin-operated arcade game but also works without it if you put it in a ordinary cartridge? --Zzo38
- You can always make a separate version for Vs. boards. It's not like you can plug a Famicom cartridge into a Vs. board or anything. But unless you're using Duck Hunt or Tennis, one problem with Vs. is that the colors are all scrambled, making it much harder to do decent fades. --Tepples 16:17, 7 October 2012 (MDT)
- The page mentions that certain revisions of the PPU (RC2C05*) return a magic number in the lower bits of $2002 read. —Lidnariq 16:47, 7 October 2012 (MDT)
- But then those are the ones that swap $2000 and $2001, so you pretty much have to make special builds for the 2C05. --Tepples 18:11, 7 October 2012 (MDT)
- If they swap $2000 and $2001 then you might be able to detect that using sprite 0 hit, somehow. Switches might also be used to configure the palettes in case 2C04 is used. Does 2C04 have any differences from 2C03 other than the colors? I know you cannot put a Famicom cartridge in the Vs. boards, but you could replace the chips manually, or make a clone hardware with the same purpose of $4016,$4017,$4020 registers (I don't know if it might be possible to build such a clone hardware into a cartridge, controller ports, and expansions ports, to wire to the coin slots and so on?). --Zzo38 18:47, 7 October 2012 (MDT)
- If you're replacing chips manually, and you know what kind of board you're replacing them into, why not just use a build specifically made for one Vs. board? I don't see the advantage of having one ROM image that runs on several fundamentally incompatible system boards. --Tepples 18:59, 7 October 2012 (MDT)
- Well I suppose yes it could be made separate ROM images, one for not Vs. System, and other for the Vs. System boards. (Using conditional compiling, perhaps?). I still was interested to know if there is ways to detect it, though. --Zzo38 19:39, 7 October 2012 (MDT)
- If you're replacing chips manually, and you know what kind of board you're replacing them into, why not just use a build specifically made for one Vs. board? I don't see the advantage of having one ROM image that runs on several fundamentally incompatible system boards. --Tepples 18:59, 7 October 2012 (MDT)
- If they swap $2000 and $2001 then you might be able to detect that using sprite 0 hit, somehow. Switches might also be used to configure the palettes in case 2C04 is used. Does 2C04 have any differences from 2C03 other than the colors? I know you cannot put a Famicom cartridge in the Vs. boards, but you could replace the chips manually, or make a clone hardware with the same purpose of $4016,$4017,$4020 registers (I don't know if it might be possible to build such a clone hardware into a cartridge, controller ports, and expansions ports, to wire to the coin slots and so on?). --Zzo38 18:47, 7 October 2012 (MDT)
- But then those are the ones that swap $2000 and $2001, so you pretty much have to make special builds for the 2C05. --Tepples 18:11, 7 October 2012 (MDT)
- Between the part where you'll need 5 additional builds (4 palette scrambles, 1 $2000/$2001 swap) to accommodate all the different Vs hardware, and only have the ability to detect the last, it's not clear to me how to feasible autodetection (as opposed to different builds, DIP switch settings, asking the user, &c)—Lidnariq 10:36, 8 October 2012 (MDT)
