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
Selecting the Operating Mode for the S7-200 CPU
Using the S7-200 Explorer
Features of the S7-200
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