Most encoders offer four signals for measuring position and velocity: channel A, channel B, channel Z, and Ground. Encoders generally produce 360 TTL pulses per revolution on channels A and B, and one pulse per revolution on channel Z, often referred to as the index pulse. The TTL pulses produced by Channels A and B are offset by 90 degrees, so that the direction of the encoder can be detected.
If you are just concerned about measuring the speed of the motor and are not concerned about the position or direction of movement, you only need to connect Channel A and the Ground signal from the encoder to the your 6024E board. You should connect Channel A to the SOURCE of Counter 0 (pin 37) and the Ground to DGND (pin 36). Using Counter 0, you can measure the frequ
ency of the signal. You can divide the frequency of Channel A by the number of pulses in one revolution of your encoder. This will provide a value that represents revolution per second, if you would like to convert that value to revolution per minute(RPM), simply multiply by 60 and you will have the speed of the encoder shaft in RPMs.
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