Fuji Electric SPH Series - Retain Memory Area

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Section 1 Specications
1-3-4 Retain memory area
The retain memory area is used for the auxiliary relays that are used internally in the PLC.
G
Key points:
1) In the direct addressing mode, this memory area is specied in he format of %M
o
3. ... (replace o with any of X, W, or D).
Usually, since a variable declaration is used to assign memory to an application program, you may neglect addresses in
programming. see “1-5 variables” for details.
2) The following processes are performed at cold or warm start.
3) You can select whether or not to clear this area when transferring the project.
If you select “clear,” the system cold-starts and If “not clear,” the system warm-starts.
4) The size of the retain memory area can be changed taking those of other areas into account.
For the details of memory size change, see “3-3-2 CPU memory size denition.”
Notes:
1) The CPU runs in “cold start” mode when started by the “Initial run” command of the loader and in “warm start” mode when
the system power is turned ON or started by the “Run” command of the loader.
2) In the following cases, the PLC cold-starts.
• When started up for the rst time after user ROM with different memory allocation was installed
• When started up for the rst time after memory backup error occurred
• When started up for the rst time after the resources were initialized
• When started up for the rst time after the data memory in this area was cleared
• During battery-less operation
Cold start Warm start
Standard memory Reset to 0 (zero).
Retains old values.
Initialized standard memory Writes specied initial values.
Retains old values.
(Note)
……………………………………………
Retain memory
(M)
15……………………………0
Unit with 14/24 points
: 2K words
Unit with 32/40/60 points
: 4K words
%MW3.0
IEC representation