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Spinners: how they work
KevSteele:
Spinners are basically single-axis mice, and work the same way as a mouse for detecting movement - they have a optic boards that have both a light emitter and detector, which detects interruptions in the light when something passes in front of it (like the "teeth" on an encoder wheel)
The optic encoder not only detects the interruptions in the optic sensors, it's able to determine which way the wheel is moving, something very important, I'm sure you'd agree. ;)
I believe this is where the "dual optical pickup" comes in, as the encoder has to compare the two optics on the optic board and see which one is turning on first, and how fast they're "strobing."
You defintiely need some sort of optical encoder to use a spinner - your current choices are the Oscar USB mouse board, or the Ultimarc Optipac or MiniPac (which combines a keyboard and optic encoder in one unit) The SlikStik Tornado comes with it's own encoder built into the optic board.
I don't want to come across as a "promotion machine" here, but you might want to check out the "Spinner Roundup" I have on my site, as it has comparisons between seven different spinners:
http://www.retroblast.com/reviews/roundup.html
and my Tornado review:
http://www.retroblast.com/reviews/tornado.html
I'll slink off now...
Kevin
ErikRuud:
The biggest difference between a real spinner and a keyboard emulated one is "velocity".
A real spinner not only gives directional control, but also velocity control.
You can spin the spinner fast or slow and the game respond accordingly. With a keyboard you only get directional control and a fixed velocity.
Hokking a spinner into a keyboard emulator would require a whole ne interface circuit, and I doubt that you could get the velocity part to work right.
For DOS, you can use a ps/2 or serial mouse hack for the spinner. When I ran on a dos based machine, I had a PS/2 trackball and a spinner that was based on a serial mouse hack.
I still use them on my upgraded machine that runs under windows.
Lilwolf:
btw, what I ment is down more of a hardware level.
the optics will 'click' for each opening in the wheel... per turn. So if you hooked the optics up directly to the ipac, it would try to send 120+ clicks per mouse move...
I was trying to say that they are apples and oranges... just doing a very bad job....
anyway.. hacks are based on this
boolean / digitial - hack to a keyboard encoder.
trackball / 360 wheel / spinner - hack to a mouse
270 wheel / analog controller - hack to a joystick.
Gideon:
--- Quote from: ErikRuud on April 20, 2004, 01:40:12 pm ---The biggest difference between a real spinner and a keyboard emulated one is "velocity".
A real spinner not only gives directional control, but also velocity control.
--- End quote ---
Okay, I understand this. But, because this is all digital, isn't the velocity just an illusion? It seems to me that velocity could be simulated in a spinner keyboard encoder as the frequency of keystrokes. Maybe not, though.
But, it's cool. I appreciate each of the work-arounds, links, and solutions you all brought up.
Here's how I'm seeing it now: If I am to compare a spinner to two keyboard buttons, I'll have to understand that the keyboard buttons operate on a fixed velocity. This is determined by the repeated key press rate of the OS or whatever. The optical encoder of a spinner works in much the same way--detecting a "press" either left or right--only it changes the "repeated key press" rate in order to match the latest velocity of the actual, turning wheel. The rate is dynamic because, well, it's a wheel--not a button.
But, it still goes binary at some point, and a keyboard press is binary... so, I was hoping...