Siemens DP/AS-Interface Link 20E

Glossary
155
DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
E.2 Terms Relating to PROFIBUS
Bus parameter
Bus parameters control the way in which data is transmitted on the bus. Each –>
station on –> PROFIBUS must use bus parameters that match the bus parame-
ters of the other stations.
CLEAR mode
Mode of the DP master. Inputs are read cyclically, outputs remain set to 0.
CP
Communications processor: Module for communications tasks for installation in
computers or programmable logic controllers.
Device database
Device database data (in a GSD file) contain DP slave descriptions complying
with EN 50170, Vol 2. The use of DDB makes it easier to configure the –> DP
master and –> DP slaves.
Distributed peripheral I/Os (DP)
Input and output modules used in a distributed configuration by the CPU (central
processing unit of the controller). The programmable logic controller and the dis-
tributed I/Os are connected via the
–> PROFIBUS bus system. For the programmable logic controllers, there is no
difference between these I/Os and local process inputs or process outputs.
DP master
Active station on –> PROFIBUS that can send frames unsolicited when it is in
possession of the token .
DP master system
A –> DP master and all the –> DP slaves with which this DP master exchanges
data.