Eaton easyControl EC4-200, User Manual

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10/10 MN05003003Z-EN
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9 Operation
General
Overview of memory sizes
The following maximum memory/POUs are available:
Memory definition
The controller has the following memory:
• Working memory (SRAM), not retentive.
– Content, e.g. program, data
• System memory (FLASH), retentive.
– Content, such as boot project
• Memory card
– Content such as boot project, operating system.
Startup behaviour
The controller does not have a battery for backing up the working
memory containing the program. To save the program in the event
of a power failure, you should create a boot project of this program
that can be stored in the retentive system memory.
After the power supply is switched on, the CPU carries out a self-
test of the system. In the event of a fault, the LEDs RUN/STOP/SF
and CAN/NET LEDs will flash red. After the self-test has been
completed fault free, the controller checks whether:
• an operating system update is present on the fitted memory
card. In this case, it must be loaded.
• a boot project is present. In this case it is loaded into the
working memory of the controller and started according to the
startup behaviour set. If no boot project is present, the
controller stays in the NOT READY state.
Startup behaviour with boot project on the memory card
When the controller is switched on, a boot project on the memory
card has priority over a project stored in the system memory.
If both projects are different, the boot project of the memory card
is copied to the system memory and then started. Due to the copy
process the PLC start-up phase will be extended by a few seconds.
Program (Code) 256 kByte
Global variables (Global) 224 kByte
Data memory (Memory) 16 kByte
Input image (Input) 4 kByte
Output image (Output) 4 kByte
Retentive variables (Retain) 8 kByte
Max. number of POUs Approx.2000
h
If a variable is declared as RETAIN in a function block (FB),
all the variables in this function block have the RETAIN
status.