Communications Setup and Operation Teledyne API T803 CO2/O2 Analyzer Operation Manual
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Example Read/Write Definition window:
Example Connection Setup window:
Example MODBUS Poll window:

6.5.2. HESSEN

The Hessen protocol is a multidrop protocol, in which several remote instruments
are connected via a common communications channel to a host computer. The
remote instruments are regarded as slaves of the host computer. The remote
instruments are unaware that they are connected to a multidrop bus and never
initiate Hessen protocol messages. They only respond to commands from the
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