EM-08 · Chapter 8 · Low-Speed Interfaces & Embedded Hardware
Direction from a rotary knob
A volume knob uses a mechanical rotary encoder with two contact outputs, A and B, 90° apart. Design a circuit that outputs 1 when the knob turns clockwise and 0 when it turns counter-clockwise.
| Level | ●● onsite technical |
| Track | Embedded & wearables |
| Really testing | Quadrature decoding — plus contact bounce. |
Full worked answer: in the book, page 216 — what to say first, how to explain it, the numbers worth quoting and the follow-ups. About the book →
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