Omron CJ2 CPU UNIT SOFTWARE User Manual

9 PLC Setup
9-6
CJ2 CPU Unit Software User’s Manual
z IOM Hold Bit Startup Hold Setting
Use this parameter to set whether to retain the status of the IOM Hold Bit in the Auxiliary Area at
startup.
• Relation between IOM Hold Bit and this Parameter
The IOM Hold Bit (A500.12) can be turned ON to retain all of the data in I/O memory when the CPU
Unit's operating mode is switched from PROGRAM mode to RUN or MONITOR mode, and vice
versa. When the PLC is turned ON, the IOM Hold Bit itself will be turned OFF unless it is protected
with this PLC Setup setting.
If the IOM Hold Bit Status at Startup setting is ON, the status of the IOM Hold Bit will be protected
when the PLC is turned ON. If this parameter is set to ON and the IOM Hold Bit itself is ON, all data
in I/O memory will be retained when the PLC is turned ON.
If the memory is not retained because the battery voltage is low, the IOM Hold Bit will be cleared
whether this parameter is set to ON or OFF.
Parameter Settings Default Function
Related flags
and words
IOM Hold Bit
Startup Hold
Setting
OFF: Cleared
ON: Retained
OFF This setting determines whether the status of the
IOM Hold Bit (A500.12) is retained at startup.
When you want all of the data in I/O Memory to
be retained when the power is turned on, turn ON
the IOM Hold Bit and set this setting to ON.
A500.12 (IOM
Hold Bit)
OFF: Forced Status Hold Bit cleared at startup
Power
OFF
Power
OFF
Power
ON
Power
ON
Forced bit status Forced bit status
Forced Status
Hold Bit: ON
Forced Status
Hold Bit: OFF
Not retained
when power is
turned ON.
ON: Forced Status Hold Bit protected at startup
Forced bit status
Forced bit status
Mode switch Retained
Power ON
Retained
Power ON
Not retained
Retained when
power is turned
ON.
Mode switch Retained
Forced Status
Hold Bit: ON
Forced Status
Hold Bit: ON

Omron CJ2 CPU UNIT SOFTWARE Specifications

General

Brand	Omron
Model	CJ2 CPU UNIT SOFTWARE
Category	Software
Language	English