Technical data

AS-Interface (AS-i)
1-7
SIMATIC NET AS-Interface – Introduction and Basic Information
C79000-G8976-C089/03
Addressing Mode
AS-i slaves are available with the following addressing modes:
S Standard slaves
Standard slaves each occupy one address on the AS-Interface. Up to 31
standard slaves can be connected to the AS-Interface.
S Slaves with the extended addressing mode (A/B slaves)
Slaves with the extended addressing mode can be operated in pairs at the
same address with an extended AS-i master. This doubles the number of
addressable AS-i slaves to 62.
One of these AS-i slaves must be programmed as an A slave using the
addressing unit and the other as a B slave. Due to the address expansion, the
number of binary outputs is reduced to three per AS-i slave.
A slaves can also be operated with a standard AS-i master (see also Section
4.2.3)
For more detailed information about these functions, refer to the AS-i master in
the previous section.
Analog Slaves
Analog slaves are special AS-i standard slaves that exchange analog values with
the AS-i master. Analog slaves are available with the following profiles:
S Analog slaves complying with profile 7.1/7.2
Analog slaves complying with profile 7.1/7.2 require special program sections in
the user program (drivers, function blocks) that execute the sequential transfer
of analog data.
S Analog slaves complying with profile 7.3/7.4
Analog slaves complying with profile 7.3/7.4 are intended for operation with
extended AS-i masters. The extended AS-i masters handle the exchange of
analog data with these slaves automatically. No special drivers or function
blocks are required in the user program.