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Introduction to PROFIBUS DP
• PROFIBUS-DP
• PROFIBUS-DP is a protocol optimized for speed which was specially designed for communication
between PLCs (DP masters) and distributed I/Os (DP slaves).PROFIBUS-DP is a low-cost,
flexible substitute for transmission of signal.
• PROFIBUS-DP is based on DIN 19245 Part 1 and the user-specific extensions in DIN 19245 Part
3. In the course of the European fieldbus standardization process, PROFIBUS-DP was integrated
into the European fieldbus standard
EN 50170.
• Master Devices PROFIBUS makes a distinction between master and slave devices. The
PROFIBUS masters are in charge of data traffic on the bus. A master can send messages without
being requested to do so, provided it is in possession of the token that entitles it to access the bus.
Masters are also referred to as active nodes in the PROFIBUS protocol.
• Slave Devices PROFIBUS slaves are simple I/O devices, such as actuators, sensors,
transducers, etc. They do not receive the token, that is. they can only acknowledge the receipt of
messages or send messages (data) to a master on request. Slaves are also referred to as passive
nodes.
SITRAIN
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