Questions about analog settings

[spidermonkey]

I don't fully understand the analog settings in MAME. For starters,I'm pretty sure I do understand the "reverse" , "return to center" and "sensitivity" adjustments. The settings that I don't understand are "Key/Joy speed" (what does increasing/decreasing this setting cause ?) I also don't understand "X" and "Y". Would "X" be the primary control ie. steering wheel and "Y" would be the secondary control ie. pedals ?   Or is "X" and "Y"  nothing more then the two directions that a single controller performs ie horizontal/vertical ? My last question is what does turning off the "mouse acceleration" in Windows achieve ? I see posts all the time about turning off the mouse acceleration for most analog games but I don't know what it causes mainly because I don't know what mouse acceleration is. Thanks for the help on all or any one of these questions.

[Minwah]

The settings that I don't understand are "Key/Joy speed" (what does increasing/decreasing this setting cause ?)

This is for when using keys instead of analog controls.  ie how fast the analog movement is simulated while holding down a key.  I read recently that this can also affect analog controls, although in theory it shouldn't!

I also don't understand "X" and "Y". Would "X" be the primary control ie. steering wheel and "Y" would be the secondary control ie. pedals ?   Or is "X" and "Y"  nothing more then the two directions that a single controller performs ie horizontal/vertical ?

Basically the latter: X is the X (horizontal) axis, Y is the Y (vertical axis).

My last question is what does turning off the "mouse acceleration" in Windows achieve ?

Mouse acceleration is a Windows (or other modern OS setting)...as you move the mouse it gradually accelerates in speed (even if moving the mouse physically at constant speed).  No arcade games (afaik) used mouse acceleration, so enabing it can confuse the game somewhat, or at least have unwanted effects.

Perhaps someone has a better technical explanation, that's the way I see it...

[spidermonkey]

Thanks Minwah. You explained all three issues perfectly and I now understand.