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Note that a Scan Period of 0 milliseconds is (and also Response Timeout and Interpoll Delay of 0) is used to obtain the maximum HART scan rate, but actual communication delays are determined by built-in timing required by the HART protocol, which makes the effective scan rate about 2-3 polls per second. Any non-zero Scan Period will or Interpoll Delay will add additional poll delay beyond the timing required by the HART protocol, and a non-zero Response Timeout will increase delay on timeouts.
Although in the example above the Master Channel is only scanning for HART CMD 03 continuously, the other polls in the HART FieldUnit's Poll Table may be requested on demand using the device's Command Register (see RediGate-HART-Master).
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