Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 293

I/O Memory Areas
Auxiliary Area (AR)
Temporary Relay Area (TR)
Data Memory Area (DM)
Word
H511
The Auxiliary Area contains flags and control bits used to monitor and control
PLC operation. This area is divided into two parts: A000 to A447 are read-
only and A448 to A959 can be read or written. Refer to 8-11 Auxiliary Area for
details on the Auxiliary Area.
Word
A447
A448
A959
The TR Area contains bits that record the ON/OFF status of program
branches. The TR bits are used with mnemonics only.
The DM Area is a multi-purpose data area that can be accessed in word-units
only (16-bit words). These words retain their content when the PLC is turned
ON or the operating mode is switched between PROGRAM mode and RUN or
MONITOR mode.
15
15
Read-only area
Read-write area
Section 8-2
Bit
Bit
257