
2.CYCLIC TRANSMISSION DESCRIPTION B-63434EN/02
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2.2.2.2 Static DI data allocation of common memory area 2
This allocation method fixes the DI data area. With this method, an
area larger than that allocated with the dynamic allocation method can
be allocated in the PMC area.
Only node status information can be read by dynamic change.
Procedure
Set the following parameters beforehand:
1) Pa42: Allocation address (for DI)
2) Pa43: Area 2 data exchange condition allocation address
3) Pa44: Switch flag allocation address
4) Pa45: Area 2 static allocation start address
5) Pa46: Area 2 static allocation data size (in words)
Organization of area 2 data exchange condition allocation:
2222<, )'=$1+
2222< )**-:%/)+'-;
2222< ##-%>:%/)+'-;
2222<5 )**-:%/)+'-;
Note) This function does not use the hatched portions.
Procedure of node information change by the user program:
The node information on the specified node can dynamically be
checked using the following procedure:
1) The user program specifies the following in the PMC D area
specified by Pa43 (area 2 data exchange condition allocation
address):
- Node number
2) Then, the user program writes FFh to the area (switch flag) in
the PMC R area specified by Pa44 (switch flag allocation
address).
3) The CNC monitors the switch flag at all times. When FFh is
written, the node number, and DO offset set in the PMC D area
are taken in as internal information, and the switch flag is set to
00h. At this time, the CNC once updates the specified node
status information according to the new settings before the
switch flag is set to 00h. So, the user program can read the
status information immediately after checking that the switch
flag is set to 00h.
4) Until FFh is written to the switch flag, the user program can read
the node information of a specified node number from the R area
or the D area.
5) Until FFh is written to the switch flag, the CNC writes the node
information of a specified node number to the specified area in
the PMC R area or D area. The DI data can be read regardless
of whether the switch flag is set to 00h.