Siemens DP/AS-Interface Link 20E, Руководство пользователя

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Using the Command Interface
120
DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
3.3.28 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 remaining 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
Byte Meaning
0 Command number: 40
H
1 Slave address
2 Number of parameter bytes
3 String byte (1)
4 String byte (2)
... .....
String byte (n-1)
... String byte (n)
Maximum value for n=220