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

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Using the Command Interface
95
DP/AS-Interface Link 20E
Release 11/2002
C79000-G8976-C138–04
3.3.14 Change_AS-i_Slave_Address
Purpose of the Command
With this call, the AS-i address of an AS-i slave can be modified.
This call is mainly used to add a new AS-i slave with the default address “0” to the
AS-Interface. In this case, the address is changed from “AS-i slave address old”=0
to AS-i slave address new”.
This change can only be made when the following conditions are fulfilled:
1. An AS-i slave with “AS-i slave address old” exists.
2. If the old AS-i slave address is not equal to 0, then an AS-i slave with address 0
cannot be connected at the same time.
3. The “AS-i slave address new” must have a valid value.
4. An AS-i slave with “AS-i slave address new” must not exist.
Note: When the AS-I slave address is changed, the AS-i slave is not reset, in other
words, the output data of the AS-i slave are retained until new data are received at
the new address.
Structure of the Job Data in the Send Buffer
Byte Meaning
0 Command number: 0D
H
1 Slave address old
2 Slave address new