Omron CJ - PROGRAMMING MANUAL 12-2009 Programming Manual page 274

Manipulating Files
Task protecting data during program replacement
(Cyclic task number 31, standby status at startup)
Always ON Flag
AUTOEXEC.OBJ
First Cycle Flag
Memory Card
Detected Flag
234
Example Program 2
Store program files for several devices and the program file for automatic
transfer at startup (AUTOEXEC.OBJ or REPLACE.OBJ (see note)) in a Mem-
ory Card. When the PLC is turned ON, the automatic transfer at startup file is
read and that program is replaced later with a program file for a different
device.
Note REPLACE.OBJ is supported only by CS/CJ-series CPU Unit Ver. 2.0 or later.
Processing that determines
the type of device connected
and stores the corresponding
file name. In this example, the
file name "ABC" is written in
A654 to A657.
Replacement
Start Bit
Processing to pro-
tect data before pro-
gram replacement
begins
IOM Hold Bit
Outputs to required
loads during pro-
gram replacement.
ABC.OBJ
Overwrite
Section 5-2