Mouse wheel. How do I replace optical encoder with rotary encoder? Answered
I have a Belkin Nostromo N52 controller. It has a mousewheel that can be custom programmed independently from the wheel in your regular mouse. I want to use it as a jog dial so I want to remove it from the original place and replace the rubber wheel with a jog dial. Basically it is to rotate the wheel 90 degrees as they did here with a mouse:
The problem is the Nostromo wheel uses an optical encoder instead of a rotary encoder (the typical used by half of the mouse wheels in the world).
The mod I want to do would be a little complicated using the optical encoder (I would have to use a piece of PCB perpendiculary soldered to the main PCB and the height of the resulting device would be very tall for what I want) but it would be very easy if I could replace the optical encoder with a rotary encoder I salvaged from a mouse since it can be laid down on the PCB pretty well.
The problem is the signals of the optical encoder and the signals of the rotary encoder are different. The middle leg of the receiver in the optical encoder is connected to +5vcc while the outputs are connected to ground using 10KΩ resistors. In the rotary encoder, the first leg is connected to ground and the other two go directly to the mouse IC.
I tried to remove the optical encoder of the Nostromo and connect the two outputs of the rotary encoder to where the outputs of the IR detector go and the third leg to ground but all I get is a permanently actived scroll down (as if the wheel was scrolling down all the time). I didn't dare to connect the third leg to Vcc just in case I blow the thing.
I think there must be a way to replace the optical encoder with a rotary encoder and get the same signals and I think this involves using the Vcc line and resistors but since I'm not very good at the electronic side of things, I don't know how to do it.
I'm enclosing a diagram of the optical encoder circuit. The diagram on the right enclosed in question marks is what I guess would be the equivalent circuit for the rotary encoder but I'm not sure. Can anybody confirm it or point out the appropriate corrections?