Plc Concepts - Siemens Simatic S7-200 System Manual

PLC Concepts

The basic function of the S7-200 is to monitor field inputs and, based on your control logic, turn on or off
field output devices. This chapter explains the concepts used to execute your program, the various types
of memory used, and how that memory is retained.
In This Chapter
Understanding How the S7-200 Executes Your Control Logic
Accessing the Data of the S7-200
Understanding How the S7-200 Saves and Restores Data
Storing Your Program on a Memory Cartridge
Selecting the Operating Mode for the S7-200 CPU
Using Your Program to Save V Memory to the EEPROM
Features of the S7-200
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