gmg@hcx.uucp (Greg M. Garner) (11/12/88)
I just noticed I made an error in the circuit I had to change mouse quadrature signals to a binary count. Here is the correct way to do it: T flip flop +5 T flip flop. _________ Q0 out | _________ | | | _______ | | | LEFT* ----------| Clock Q |----| \ \ \ |--| T Q |--- Q1 out | | |----| | \_____| | | | |---| | / | CLOCK | +5--------| T | | / /______/ | | |_________| | |_________| | RIGHT* These are edge triggered T flip flops. This circuit acts like a counter which will keep track of the position of the mouse at all times. This particular circuit is only able to count up to 3, then it rolls over to 0 again, (outputs at Q0 and Q1), but it will count up when the mouse is rolling left, and count down when it is rolling right (I may have these reversed). If you want to add more resolution, just repeat the part of the circuit on the right, extending it out to as many bits as you might need. You may also be able to use a binary counter that has a up/down input (like the 74ls193 I think), and implement the circuit in fewer gates. Just repeat this same circuit for the forward/back part of the mouse, and presto chango, you have a mouse driven position sensing device. Greg Garner gmg@hcx.uucp path: ...!uunet!harris.cis.ksu.edu!hcx!gmg 501-442-4847 /* Sorry about the errors, but I am only Human! Good thing I'm not a computer , then this would have been a real mess! */