Rotary Encoder - People @ EECS at UC Berkeleyboser/courses/49... · 2018-03-07 · enc. enc. enc....

B. E. Boser 1

Electronics for IoT

Rotary Encoder

Bernhard E. BoserUniversity of California, Berkeley

boser@eecs.berkeley.edu

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Rotary Encoder

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Optical Encoder

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IR Encoder

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Counts per Revolution (CPR)

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Example: Distance Traveled

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Encoder Readout

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Limitations

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Quadrature Encoder

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Quadrature Encoder Output

Forward Reverse

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Quadrature Encoder “Decoding”

Forward Reverse

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Quadrature Decoder Output

Forward Reverse

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Decoder Readout Hardware Support

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ESP32 uPython “Decoder”

• called “ENC”

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ENC Functions

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Summary

• Encoders monitor rotation

• Only relative angle / position

• Quadrature encoders– To distinguish forward / backward

• Decoder readouta) Interrupt handler, orb) Dedicated hardware counters

Ref: http://embeddedsystemengineering.blogspot.com/2016/07/arm-cortex-m3-stm32f103-tutorial.html

IoT49: Encoder