Serial Plc Link Area - Omron CJ - 09-2009 Operation Manual

Serial PLC Link Area

Special I/O Unit Area
Initialization
1,2,3...
IOM Hold Bit Operation
9-7

Serial PLC Link Area

Forcing Bit Status
Serial PLC Link Area
Initialization
1,2,3...
The contents of the Special I/O Unit Area will be cleared in the following
cases:
1. The operating mode is changed from PROGRAM mode to RUN/MONITOR
mode or vice-versa and the IOM Hold Bit is OFF.
2. The PLC's power supply is cycled and the IOM Hold Bit is OFF or not pro-
tected in the PLC Setup.
3. The Special I/O Unit Area is cleared from a Programming Device.
4. PLC operation is stopped when a fatal error other than an FALS(007) error
occurs. (The contents of the Special I/O Unit Area will be retained when
FALS(007) is executed.)
If the IOM Hold BIt (A50012) is ON, the contents of the Special I/O Unit Area
will not be cleared when a fatal error occurs or the operating mode is changed
from PROGRAM mode to RUN/MONITOR mode or vice-versa.
If the IOM Hold BIt (A50012) is ON and the PLC Setup's "IOM Hold Bit Status
at Startup" setting is set to protect the IOM Hold Bit, the contents of the Spe-
cial I/O Unit Area will not be cleared when the PLC's power supply is cycled.
The Serial PLC Link Area contains 90 words with addresses ranging from
CIO 3100 to CIO 3189. Words in the Serial PLC Link Area can be used for
data links with other PLCs.
Serial PLC Links exchange data among CPU Units via the built-in RS-232C
ports, with no need for special programming.
The Serial PLC Link allocation is set automatically by means of the following
PLC Setup settings at the Polling Unit.
• Serial PLC Link Mode
• Number of Serial PLC Link transfer words
• Maximum Serial PLC Link unit number
CJ1M CPU
CJ1M CPU
Unit Unit
RS-232C RS-232C
port
port
Serial PLC Link
Addresses not used for Serial PLC Links can be used only in the program, the
same as the Work Area.
Bits in the Serial PLC Link Area can be force-set and force-reset.
The contents of the Serial PLC Link Area will be cleared in the following
cases:
1. The operating mode is changed from PROGRAM mode to RUN/MONITOR
mode or vice-versa and the IOM Hold Bit is OFF.
2. The PLC's power supply is cycled and the IOM Hold Bit is OFF or not pro-
tected in the PLC Setup.
3. The Serial PLC Link Area is cleared from a Programming Device.
CJ1M CPU
Unit
Serial PLC
Link Area
RS-232C
port
Section 9-7
387