Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual page 246

Glossary
Data, static
Static data can only be used within a function block. These data is saved in an instance data
block that belongs to a function block. Data stored in an instance data block are retained
until the next function block call.
Data, temporary
Temporary data represent local data of a block. They are stored in the L-stack when the
block is executed. After the block has been processed, these data are no longer available.
Default Router
The default router is the router that is used when data must be forwarded to a partner
located within the same subnet.
In STEP 7, the default router is named
default router.
Determinism
See Real Time
Device Name
Before an IO device can be addressed by an IO controller, it must have a device name. In
PROFINET, this method was selected because it is simpler to work with names than with
complex IP addresses.
The assignment of a device name for a concrete IO device can be compared with setting the
PROFIBUS address of a DP slave.
When it ships, an IO device does not have a device name. An IO device can only be
addressed by an IO controller, for example for the transfer of project engineering data
(including the IP address) during startup or for user data exchange in cyclic operation, after it
has been assigned a device name with the PG/PC .
Diagnostic buffer
The diagnostics buffer represents a buffered memory area in the CPU. It stores diagnostic
events in the order of their occurrence.
Diagnostic Interrupt
Modules capable of diagnostics operations report detected system errors to the CPU by
means of diagnostic interrupts.
Diagnostics
See System diagnostics
Glossary-4
Router
. STEP 7 assigns the local IP address to the
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05