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9-4-3. Specifying slave machine as talker from master unit
・
When the master unit sends a command requiring a response message to the slave unit and the
slave unit sends an acknowledge, a message having the structure shown in example 6 is sent to
the master unit.
<Example 6> Inquiring about the model of the PW-A power supply unit controlled in address 1.
(Command: MS3)
<Precautions>
・
The service request function must be disabled when the master unit sends a command
requiring a response message to the slave unit. Otherwise, signal collision may occur in the
PW-A transmission path.
9-4-4. Acknowledge or negative acknowledge to slave units
・
The master unit must send an acknowledge or negative acknowledge to the slave unit within 500ms
after completion of message transmission from the slave unit to the master unit.
<Example7>
If the master unit sends a negative acknowledge, the slave unit resends the same message to the
master unit.
<Example 8>
<Precautions>
・
Unless the master unit sends an acknowledge or negative acknowledge to the slave unit, the
slave unit sends a message to the master unit twice.
