Mitsubishi Electric MELSEC iQ-F Series User Manual page 25

PresentValue for the output/value object
■Writing
Internal memory
PriorityArray
Buffer memory
Value setting value
Priority
Null setting flag
Write flag
(1) When a value is written from a BACnet workstation or BACnet controllers, the Ethernet module reflects the write value in the PriorityArray in the internal
memory and calculates the PresentValue in the internal memory.
(2) After the program writes the Value setting value, Priority setting value, and Null setting flag, the write flag is turned on.
(3) When the Ethernet module detects that the write flag is on, it reads the Value setting value, Priority setting value, and Null setting flag from the buffer
memory.
The Ethernet module reflects the write value in the PriorityArray in the internal memory, and calculates the PresentValue in the internal memory.
(4) The Ethernet module turns off the write flag.
(5) When the Null setting flag is on, Null is written to PriorityArray.
Write control is an alternative to WriteProperty and a value can be written even during OutOfService.
However, the written value is not reflected in the buffer memory, and the write counter is not incremented.
When OutOfService changes from TRUE to FALSE, the written value is reflected in the buffer memory.
Even if the value is written multiple times during OutOfService, the update flag is incremented by 1.
Writing data from BACnet
workstation or another
BACnet controller
(1)
Value = 2
Priority = 16
Idx Value Idx
1 Null 1
8 Null 8
16 Null 16
Default 1 Default
PresentValue = 2 PresentValue = 2
-
-
OFF
OFF
Writing data from the
program
Value = 5
Priority = 8
Value Idx Value
Null 1 Null
Null 8 5
2 16 2
1 Default 1
PresentValue = 5
(3)
5
8
ON
(2)
(4)
OFF
Writing Null from the
program
Value = Null
Priorit = 16
Idx Value
1 Null
8 5
16 Null
Default 1
PresentValue = 5
-
16
(5) ON
ON
OFF
4 FUNCTIONS
4.2 BACnet Object Function
4
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