Technical data

Table Of Contents
System Software for S7-300/400 System and Standard Functions - Volume 2/2
A5E00739858-01
33-1
33 System Status Lists (SSL)
33.1 Overview of the System Status Lists (SSL)
This chapter describes all the partial lists of the system status list that relate to the
following:
CPUs
Modules whose partial lists are not module-specific (for example, SSL-IDs
W#16#00B1, W#16#00B2, W#16#00B3).
Module-specific partial lists, for example, for CPs and FMs are included in the
descriptions of the particular modules.
Definition: System Status List
The system status list (SSL) describes the current status of a programmable logic
controller. The contents of the SSL can only be read using information functions
but cannot be modified. The partial lists are virtual lists, in other words, they are
only created by the operating system of the CPUs when specifically requested.
You can only read one system status list using SFC 51 "RDSYSST."
Contents
The system status lists contain information about the following:
System data
Module status data in the CPU
Diagnostic data on modules
Diagnostic buffer
System Data
System data are fixed or assigned characteristic data of a CPU. They provide
information about the following:
The configuration of the CPU
The status of the priority classes
Communication