SEW MOVIDRIVE MDX60B, User Manual

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Manual – MOVIDRIVE® MDX60B/61B Communication and Fieldbus Unit Profile
4
MOVILINK® protocol via RS485 transmission method
Serial Interfaces of MOVIDRIVE® B
Structure of the
request telegram The following figure shows the structure of the request telegram, which the master
sends to the inverter. Each telegram starts with an idle time on the bus, the so-called
start pause, followed by a start delimiter. Different start characters are used to clearly
distinguish between request and response telegrams. The request telegram begins with
the start character SD1 = 02hex, followed by the slave address and PDU type.
Structure of the
response telegram The following figure shows the structure of the response telegram, which the inverter
(slave) sends as response to a request from the master. Each response telegram begins
with a start pause, followed by a start delimiter. To clearly distinguish request and re-
sponse telegrams, the response telegram begins with the start character SD2 = 1Dhex,
followed by the slave address and PDU type.
Start characters
(SD1 / SD2) The start character identifies the beginning and direction of data of a new telegram. The
following table depicts the assignment of start character to direction of data.
01485BEN
....Idle...
SD1
ADR TYP PDU BCC
Start delimiter 1
02 hex
PDU type
Block check character
Start pause Slave address Protocol data unit
01487BEN
....Idle...
SD2
ADR TYP PDU BCC
Start delimiter 2
02 hex PDU type
Block check character
Start pause Slave address Protocol data unit
SD1 02
hex
Request telegram Master
→
inverter
SD2 1D
hex
Response telegram Inverter
→
master