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Review: Paradise Arcade Shop 2 1/4'' Trackball
DaOld Man:
Good idea!
wizkid32:
Plain white paper is not fully opaque. It would still let a little light through. As for the brightness, it should be perfect for my theme.
BobA:
About the leds always on problem: I connected the tb to a ps2 usb adapter and the leds go off when the computer is off. The bad is that a simple adapter does not allow the TB to function. You probably need and active adapter that costs a few bucks more.
DaOld Man:
I plugged the TB directly into the PS2 mouse port of the motherboard. Im thinking it is a motherboard specific thing.
I have done a little research on the way this trackball lights up (for hacking purposes.)
The two pairs of LEDs (one red pair and one green pair) are controlled by a HEF4049BP hex inverter.
Looks like the inverters are wired to either turn on or off the pairs of leds, based on a high being at the input of the first two inverters. 3 diodes isolate the 3 button inputs. If either button is pressed, green leds are turned off and red leds are turned on. (Pin 10 on the chip is not connected to anything).
I have attached a diagram that i drew showing the specs for the HEF4049BP hex inverter and below that, the way this trackball is using the chip to light the LEDs (best I can tell anyway).
The diodes block the button clicks from each other, however supply a high to the inverters whenever either button is pressed.
The resistors (Rx(0) thru Rx(2) are evidently current limiters, and Rx(3) thru Rx(5) are pull down resistors.
Now I have two questions which hopefully you can help me with Bob.
(1) what is pulling the voltage down on the input side of the inverters? (Wouldnt the voltage float?)
(2) why arent there current limiting resistors on the leds? (none that I can find).
DaOld Man:
The last print was a little small, here is the TB led circuit again. Maybe a little easier to read now.
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