Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 345

Data Memory (DM) Area
DM Area Allocation to
Special Units Inner Board
1,2,3...
Parts of the DM Area are allocated to Special I/O Units, CPU Bus Units, and
Inner Boards for functions such as initial Unit settings. The timing for data
transfers is different for these Units, but may occur at any of the three follow-
ing times.
1. Transfer data when the PLC's power is turned on or the Unit is restarted.
2. Transfer data once each cycle.
3. Transfer data when required.
Refer to the Unit's Operation Manual for details on data transfer timing.
Special I/O Units (D20000 to D29599)
Each Special I/O Unit is allocated 100 words (based on unit numbers 0 to 95).
Refer to the Unit's Operation Manual for details on the function of these
words.
Special I/O Unit
Data trans-
ferred to the
Special I/O
Unit when the
PLC is turned
ON or the Unit
is restarted.
Data trans-
ferred to the
CPU Unit at
cyclic refresh-
ing or when
necessary.
CPU Bus Units (D30000 to D31599)
Each CPU Bus Unit is allocated 100 words (based on unit numbers 0 to F).
Refer to the Unit's Operation Manual for details on the function of these
words. With some CPU Bus Units such as Ethernet Units, initial settings must
be registered in the CPU Unit's Parameter Area; this data can be registered
with a Programming Device other than a Programming Console.
CPU Bus Unit
Data trans-
ferred to the
CS1 Special
Unit when the
PLC is turned
ON or the Unit
is restarted.
Data trans-
ferred to the
CPU Unit at
cyclic refresh-
ing or when
necessary.
CPU Unit
DM Area for Special I/O Units
(100 words/Unit)
CPU Unit
DM Area for CPU Bus Units
(100 words/Unit)
Section 8-15
309