
2.CYCLIC TRANSMISSION SPECIFICATION B-64164EN/01
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2.2.2.2 DI data allocation
Whether to perform dynamic allocation or static allocation of DI data
of common memory area 2 can be specified by the setting of Pa46
(allocation size (for DI)).
Dynamic DI data allocation of common memory area 2
The user program switches to the DI data area for a target node and
reads the DI data for the node. By specifying a node number, the DI
data from the node and status information of the node can be read.
Related parameters
(1) Pa42: PMC start address (for DI)
(2) Pa43: Allocation condition setting (for DI/DO)
(3) Pa44: Condition switch flag (for DI/DO)
(4) Pa46: Allocation size (for DI) = 0
(5) Pa61: Bit 2 (DTL) of parameter 2 = 1
Allocation condition setting organization
Organization of area 2 data exchange condition allocation:
7 0
Dxxxx+0 Node number
Dxxxx+2 DI offset (in words)
Dxxxx+4 Data size (in words)
Dxxxx+6 DO offset (in words)
NOTE
The parts except the shaded part are not used by
this function.
Procedure
Procedure for changing dynamic DI allocation of common memory
area 2 by using the user program:
(1) The user program specifies the following in the PMC D area
specified by Pa43 (allocation condition setting (for DI/DO)):
- Node number
- DI offset
- Data size
(2) Then, the user program writes FFh to the area (switch flag) in the
PMC E area or the PMC R area specified by Pa44 (condition
switch flag (for DI/DO)).
Pa43→