Siemens S7-300 appendix Data, temporary, Default Router, Determinism, Device Name

Glossary

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 .

Glossary-4	CPU 31xC and CPU 31x, Technical data
	Manual, Edition 08/2004, A5E00105475-05