Siemens SIMATIC Distributed I/O System DP/ASi Link, Руководство пользователя

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Glossary-5
Distributed I/O System DP/ASi Link
EWA 4NEB 710 6055-02b
Draft PROFIBUS-DP standard (EN 50170 Volume 2, PROFIBUS), on which
the Distributed I/O System is based.
The principal function of PROFIBUS-DP is high-speed data exchange be-
tween the central DP master and the I/O devices.
PROFIBUS-DP is a bus system networking PROFIBUS-compatible program-
mable logic controllers and field devices at field and cell levels. PROFIBUS-
DP is available with DP (
+
Distributed I/O), FMS (
+
Field Bus Message
Specification) or TF (
+
Technological Functions) protocols.
R
You set the length of the response monitoring time with the configuration
software of the DP master.
If a DP slave is not addressed within the response monitoring time, it enters
the safe state, i.e. all outputs are set to ”0”.
S
By setpoint configuration we mean the configured set-up of the ASi as stored
in the DP master.
A slave may exchange data with a
³
master only when requested to do so by
the latter.
A station is a device which can send, receive or amplify data over the bus –
for example, a master, slave, repeater or coupler.
Station diagnostics is the highest level of slave-specific diagnostics. It refers
to the whole slave.
Every PROFIBUS-DP node must be given a station number. The programmer
and the ET 200 Handheld are addressed with the station number ”0”; DP
masters and DP slaves have a station number in the range from 1 to 125.
PROFIBUS-DP
Response
monitoring time
Setpoint
configuration
Slave
Station
Station
diagnostics
Station number
Glossary