Bus Accessing Mode; Data Exchange Via Profibus-Dp - Siemens COMBIMASTER 411 Operating Instructions Manual

DEFINITION
bus terminators can normally be activated either in the devices themselves or on
the bus termination connectors.
To accommodate more than 32 nodes or increase the scope of the network,
repeaters (cable amplifiers) can be installed to link the individual bus segments.
2.2.2

Bus accessing mode

PROFIBUS operates according to the token passing principle, i.e. the active
stations (masters) receive transmit authorization in a logical ring for a defined time
window. Within this window, the master can communicate with other masters or
exchange data with the relevant slaves in a subordinate master-slave process.
PROFIBUS-DP primarily utilizes the master-slave process for this purpose; in most
cases, it exchanges data with drives such as MICROMASTER 4 cyclically.
2.3

Data exchange via PROFIBUS-DP

Data can be exchanged between the higher-level systems (e.g. SIMATIC,
SIMADYN D, PC/PGs) and the drives very quickly via the PROFIBUS-DP. Drives
are always accessed according to the master-slave principle. Drives are always
slave nodes. Each slave can be identified by its unique address on the bus (MAC).
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PROFIBUS Communication Module
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Operating instructions
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