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Command Interface
5-54
SIMATIC NET CP 243-2 AS-i Master
C79000-G8976-C142/02
5.2.28 Write_AS-i_Slave_Parameter_String
Purpose
With this call, a parameter string complying with AS-i slave profile 7.4 can be sent
to the AS-i master that passes on the string to the AS-i slave address specified in
the send buffer.
With this call, a send buffer with a maximum of 223 bytes is transferred to the AS-i
master. The actual number of parameter bytes to be sent to the AS-i slave is
calculated by the AS-i master from byte 2 of the send buffer (number of parameter
bytes).
The information in the string is not evaluated by the AS-i master and is passed on
to the AS-i slave transparently.
As long as the string transfer is active, there is no user/analog data exchange with
the addressed AS-i slave.
Structure of the Job Data in the Send Buffer
Bank Byte Meaning
2 0 40
H
2 1 Slave address
2 2 Number of parameter bytes
2 3 String byte (1)
2 4 String byte (2)
... ... .....
... ... String byte (n–1)
... ... String byte (n)
Maximum value for n=220
Structure of the Job Data in the Receive Buffer
Bank Byte Meaning
2 0 Echo of the command number: 40
H
2 1 Command status