Panasonic KX-T7456 - Digital 24 Button Speakerphone Display, Specifications

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7.7. JOG DIAL CIRCUIT
1) Circuit Operation
This unit is equipped with the JOG switch, which makes the settings of the volume, function
selection speed dial, etc. easy and convenient. This JOG switch consists of 2-phase rotary
encoder, and the gate array of IC1 counts the number of the rotation to control. The sampling
cycle is 1ms and provided with the chattering protective circuit whose available pulse width is
1ms or more.
These are the rotary encoder inputs, and sampled 1 kHz (1 msec)/cycle. The built-in chattering
protective circuit neglects the input pulse of 1 msec or less. The high pulse of 2 msec or more is
available. The availability of the pulse with the width of 1~2 msec is not ensured.
The changed number of these 2-phase inputs is counted cumulatively. The maximum counting
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