1) How to calculate encoder resolution 

Resolution is one of the most important indicators of an encoder’s performance. For incremental encoders, resolution is typically specified in pulses per revolution (PPR), or, in the case of linear encoders, pulses per inch (PPI) or pulses per millimeter (PPM). These square-wave pulses are very precisely spaced, and the encoder determines its position by counting the number of pulses generated during a movement.

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