mouse button LED circuit

[flood]

chief, could you provide details for the mouse modification mentioned here?
http://www.blurbusters.com/gsync/preview2/

Did you just hook up wires to the button sensor or to the usb cable?

[Chief Blur Buster]

Direct hard-wire to the button, in series with a 3V button cell for LED power supply. I opened up the mouse and soldered two wires, one on each side of the momentary button contacts for the left mouse button. Made a hole in the mouse case for these two wires. Connected the wire direct to a LED and 3V button cell. It is essentially a separate circuit loop only sharing circuit via the existing button contact in a common-ground manner with the mouse. Super duper simple, and guarantees electrical parity with the mouse button timing.

I'll sketch up a diagram this week, and post a new BlurBusters article as reviewers have asked about his technique.

[flood]

alright thanks.

I've been thinking of measuring input lag using a photodiode + that LED circuit and feeding the signals to my soundcard for timing.