Wiring an Encoder to the I-PAC
permalinkI’ve finally figured out how to wire up an encoder (ie: a knob) to a keyboard emulator like the I-PAC. Easy logic - a flip-flop, some AND and NOT gates. Extra credit: redesign this logic to replace AND and NOT with NAND.
I knew that electrical engineering degree would come in handy at some point! Here’s the waveform it produces:
As the encoder turns counter-clockwise (the first two turns), a signal on the CCW_TURN line is generated. As it turns clockwise (the last two turns), a signal on the CW_TURN line is generated. There’s a possibility that if the AND gate on the bottom left there is too fast, you might end up with a turn in the wrong direction. I’m hoping it “just works” when I build it.
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