Mitsubishi Electric MELSEC iQ-R User Manual page 33

Operation of a BACnet module
■ Operation at startup
At the startup of a BACnet module, the module writes values, which are saved in the internal memory before powering OFF
(or resetting) the module, to the STATUS in the buffer memory
*1 When "InitialDataOutputDisable" in [Settings]  [Basic Information]  [BACnet Detail Setting] button  "Interface" is set to '0', the
PresentValue property value in the internal memory is applied to the PresentValue property in the buffer memory at the startup of the
module.
■ Cyclic operation
A BACnet module periodically
internal memory.
*1 For the reading cycle, refer to the following section.
Page 264 Loading buffer memory
START
Read the CONTROL
Set the OutOfService property
*1
OutOfServicie=1
NO
Set the read value to
the Reliability property
END
*1 When '1' is set to "OutOfServiceControl" in [Settings]  [Basic Information]  [BACnet Detail Setting] button  "Interface", the value of an OutOfService
property is stored. (Page 281 Interface)
■ Operation when a WriteProperty(Multiple) service is received
• When a WriteProperty(Multiple) service is received, a BACnet module writes the PresentValue property value in the internal
memory to the PresentValue property in the buffer memory. After the value is written, '1' is written to the PVWritten of the
STATUS in the buffer memory.
• Change the PVWritten of the STATUS in the buffer memory to '0' to receive a new WriteProperty(Multiple) service. To
change the value, use the PVWrittenClear of the CONTROL.
• When a data conversion setting is configured in an object, a BACnet module stores a converted 16-bit signed integer value
to the PresentValue property in the internal memory. (Page 170 Data conversion)
When no data conversion setting is configured in an object, the value of a PresentValue property in the buffer memory is
read as a 32-bit floating point real number value, and the value is stored to the PresentValue property in the internal
memory.
Precautions
• After a WriteProperty(Multiple) service is received, a value is written to the PresentValue property and '1' is written to the
PVWritten regardless of the values of PVWritten and PVWrittenClear. (A value is written even when the value is the same
as the PresentValue property.)
*1
reads a CONTROL in the buffer memory and applies the following processing result to the
YES
*1
.
1 FUNCTIONS
1.1 BACnet Object Function
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