Siemens S7-300 GSD file, Hub, Industrial Ethernet, Instance data block, Interface, MPI-capable

Glossary

Chassis ground is the totality of all the interconnected passive parts of a piece of equipment on which dangerous fault-voltage cannot occur.

GSD file

The properties of a PROFINET device are described in a GSD file (General Station Description) that contains all the information required for configuration.

Just as in PROFIBUS, you can integrate a PROFINET device in STEP 7 using a GSD file.

In PROFINET IO, the GSD file is in XML format. The structure of the GSD file complies with ISO 15734, the worldwide standard for device descriptions.

In PROFIBUS, the GSD file is in ASCII format.

Hub

In contrast to a switch, a hub sets itself to the lowest speed at the ports and forwards the signals to all connected devices. A hub is also not capable of giving priority to signals. This would lead to a high communication load on Industrial Ethernet.

See Switch

Industrial Ethernet

Industrial Ethernet (formerly SINEC H1) is a technology that allows data to be transmitted free of interference in an industrial environment.

Due to the openness of PROFINET, you can use standard Ethernet components. We recommend, however, that you install PROFINET as Industrial Ethernet.

See Fast Ethernet

Instance data block

The STEP 7 user program assigns an automatically generated DB to every call of a function block. The instance data block stores the values of inputs / outputs and in/out parameters, as well as local block data.

Interface, MPI-capable

See MPI

Interrupt

The CPU's operating system knows 10 different priority classes for controlling user program execution. These priority classes include interrupts, e.g. process interrupts. When an interrupt is triggered, the operating system automatically calls an assigned OB. In this OB the user can program the desired response (e.g. in an FB).

Interrupt, cyclic interrupt

A cyclic interrupt is generated periodically by the CPU in a configurable time pattern. A corresponding OB will be processed.

Glossary-8	CPU 31xC and CPU 31x, Technical data
	Manual, Edition 08/2004, A5E00105475-05