http://hackaday.com/2012/01/26/analog-joypad-for-your-retro-pc/ A pot is basically an adjustable resistor. Like swimming in mud -vs- water.. Electric current flow is reduced as it passes through the resistor. This resistance is measured in Ohms. Typical arcade pots use 5 ohm pots. At its start point.. there is virtually zero resistance. The middle would be around 2.5k... and the end of travel, 5k.
In most arcade devices, they used mechanical gearing, to make the pot turn more, which creates higher resolution / sensitivity.
The full travel of the pot is rarely fully used, and it rarely needs to be set to an exact physical point or electrical value. Generally, a game will have a calibration routine you run... which registers the current centered position/value... then has you rolls the controller to its furthest points, to establish those values, to use in gameplay control.
PC controllers typically use a 100k pots. Hook the wrong value pot up, and it may not even register, and or it will not control properly. Even though most PC hardware is set to use 100k pots... some controllers have internal circuit-board convertes... so that their non standard valued pots will work.
PC wheels are a little more tricky. Some of these have both a pot value.. as well as an optical centering sensor. The optical sensor stuff was generally added for force feedback wheels.
Spring centered wheels often can get out of center alignment , as they got stressed over the years of use. Also, pots can get worn.. which would cause inaccurate readings. Force feeback motors help solve these problems, by using the FFB motors themselves, for centering the wheel... rather than merely using springs.
Hacking a pc wheel that also has the optical centering on it, isnt easy, because the parts are usually very small.. and need very high precision alignment and stability. (machine shop level accuracy)
Im not an electronics guru.. so I often use mechanical solutions. In this case, you may be able to down-gear the pot. You will lose resolution this way.. but would gain the rotational travel. The thing is.. most would prefer higher resolution with that added travel.
In such a case... theres no way to do this.. unless you know the limits of the interpreter PCBs. You dont know if its capable of registering more than its current limits... nor do you know if you can program its software drivers to accept that.
Simply modding registry entries cant overcome a limit in actual hardware specs.
Finally, the do make devices while allow full rotation to wired connections. But, the pots in your wheel are not meant to rotate 360. Also, you wouldnt want to make a typical pc spin 360. Your hardware be incapable of reading it, and the wheel probably isnt balanced nor well suited to high speed spinner rotations.. such as seen on a game of supersprint. Needs good bearings, decent mass, good balance, proper circle shape, and a good gripping shape.
360 degree wheels tend to use an optical sensor... much like a mouse wheel... to track rotation. Its possible to use these on any kind of racing / spinner game (in mame / games that allow mouse steering). The only thing is that some people do not like the fact that the wheel wont physically center, in non 360 deg games.
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Topic: Extending wheel rotation on Logitech Formula Force EX (Read 17446 times)
