Siemens Simatic S7-300 CPU 31xC and CPU 31x S7-300 - Manual (Page 220)

Glossary
CPU 31xC and CPU 31x, Technical data
Glossary-4
Manual, Edition 08/2004, A5E00105475-05
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
Router. STEP 7 assigns the local IP address to the
default router.
Determinism
See Real Time
Device
Within the context of PROFINET, "device" is the generic term for:
•
Automation systems,
• Field devices (for example, PLC, PC),
• Active network components (for example, distributed I/O, valve blocks, drives),
• hydraulic devices and
• pneumatic devices.
The main characteristic of a device is its integration in PROFINET communication over
Ethernet or PROFIBUS.
The following device types are distinguished based on their attachment to the bus:
•
PROFINET devices
• PROFIBUS devices
See PROFIBUS Device
See PROFINET Device
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 .