Siemens Simatic S7-300, Руководство по аппаратному обеспечению и установке, Страница: 223 / 242

Glossary
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
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Consistent data
Data whose contents are related and which should not be separated are known as
consistent data.
For example, the values of analog modules must always be handled consistently,
that is the value of an analog module must not be corrupted by reading it out at two
different times.
Counter
Counters are part of CPU --> system memory. The content of "Counter cells" can
be modified by STEP 7 instructions (e.g. up/down count).
CP
--> Communication Processor
CPU
Central Processing Unit of an S7 PLC, consisting of the control and arithmetic unit,
memory, operating system and a PG interface.
Cycle Time
The term cycle time describes the time required by a --> CPU for one --> user
program execution.
Data block
Data blocks (DB) are data areas in the user program which contain user data.
Global data blocks can be accessed by all code blocks while instance data blocks
are assigned to a specific FB call.
Data, static
Static data is data which can only be used within a function block. The data is
saved in an instance data block belonging to the function block. The data stored in
the instance data block is retained until the next function block call.
Data, temporary
Temporary data is local data of a block that is stored in the L stack during block
execution and no longer available after execution.
Delay Interrupt
--> Interrupt, Delay