Siemens Simatic S7-300 CPU 31xC and CPU 31x S7-300 User Manual

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Glossary

CPU 31xC and CPU 31x, Technical data

Glossary-6

Manual, Edition 08/2004, A5E00105475-05

Error response

Reaction to a runtime error. Reactions of the operating system: It sets the automation

system to STOP, indicates the error, or calls an OB in which the user can program a

reaction.

ERTEC

See ASIC

Fast Ethernet

Fast Ethernet describes the standard with which data is transmitted at 100 Mbps. Fast

Ethernet uses the 100 Base-T standard.

See Function block

See Function

Flag bits

Flag bits are part of the CPU's system memory. They store intermediate results of

calculations. They can be accessed in bit, word or dword operations.

Flash EPROM

FEPROMs can retain data in the event of power loss, same as electrically erasable

EEPROMs. However, they can be erased within a considerably shorter time (FEPROM =

Flash Erasable Programmable Read Only Memory). They are used on Memory Cards.

Force

The Force function can be used to assign the variables of a user program or CPU (also:

inputs and outputs) constant values.
In this context, please note the limitations listed in the

Overview of the test functions section

in the chapter entitled Test functions, Diagnostics and Troubleshooting in the S7-300

Installation manual.

Function

According to IEC 1131-3, a function (FC) is a --> code block without --> static data. A

function allows transfer of parameters in user program. Functions are therefore suitable for

programming frequently occurring complex functions, e.g. calculations.