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CPU Unit Memory Area
The PLC Unit utilizes a variety of different data including user programs, I/O Memory data and comments, CPU Unit and Special I/O units
Parameters, and Registered I/O Table information etc.
All of this data that is used by the PLC is stored in the memory area within the CPU unit.
The SYSMAC PLC has the following types of Memory Areas, which is backed up by a battery.
In the case of the SYSMAC CS/CJ Series, the content of the Memory Area is backed up using flash memory, which means that even if battery
power fails, any user programs and parameter area data will not be lost.
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User Program Area
This records user programs designed by the client.
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I/O Memory Area
This Area is accessed by command operands. It records information such as the CIO, Internal I/O Area, holding area, auxiliary area, DM Area,
EM Area, Timer Completion Flags/Present Value, Completion Flag/Present Value, Task Flags, Index Register, Data Register, Condition Flags,
Clock Pulse, etc. The data in the I/O Memory Area locates in or is in areas in which the contents are cleared every time the power is turned
back on, and areas in which prior information is retained. (In some areas you can select whether to clear or retain.)
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Parameter Area
This contains all of the information regarding initial parameters used by the PLC.
It records information such as the PLC System Parameters, Registered I/O Table, Routing Table, and PLC Setup for CPU Bus unit.