Disabling Special I/O Unit Cyclic Refreshing - Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual

Data Exchange with CPU Bus Units
Transferred when power is turned
on or the Unit is restarted.
FINS Commands
Serial Communications Special I/O Unit
Unit
Special I/O Unit Initialization
7-6-2

Disabling Special I/O Unit Cyclic Refreshing

242
Special I/O Unit
Transferred each cycle
and when necessary.
The CMND(490) instruction can be added to the ladder program to issue a
FINS command to the Special I/O Unit.
Special I/O Unit
FINS command transmission
FINS commands can be transmitted to Special I/O Units in other PLCs in the
network, not just the local PLC.
Serial Communications Unit
CPU Unit
FINS command transmission
Special I/O Units are initialized when the PLC's power is turned on or the
Unit's Restart Bit is turned ON. The Unit's Special I/O Unit Initialization Flag
(A33000 to A33515) will be ON while the Unit is initializing.
I/O refreshing (cyclic I/O refreshing or refreshing by IORF(097)) will not be
performed for a Special I/O Unit while its Initialization Flag is ON.
Ten words are allocated to each Special I/O Unit in the Special I/O Unit Area
(CIO 2000 to CIO 2959) based on the unit number set on the front of each
Unit. The data in the Special I/O Unit Area is refreshed in the CPU Unit every
cycle during I/O refreshing (just after execution of the END(001) instruction).
I/O refreshing may take too long if too many Special I/O Units are installed. If
I/O refreshing is taking too much time, the PLC Setup can be set to disable
cyclic refreshing for particular Special I/O Units. (The Special I/O Unit Cyclic
Refreshing Disable Bits are in PLC Setup addresses 226 to 231.)
If the I/O refreshing time is too short, the Unit's internal processing will not be
able to keep pace, the Special I/O Unit Error Flag (A40206) will be turned ON,
and the Special I/O Unit may not operate properly. In this case, the cycle time
CPU Unit
DM Area for Special I/O Units
100 words/Unit
CPU Unit
The FINS command is transmitted
when CMND(490) has been
executed in the program.
CPU Unit
The FINS command is transmitted
when CMND(490) has been
executed in the program.
Section 7-6