Siemens CP 243-2 - Manual (Page 80)

Command Interface
5-12
SIMATIC NET CP 243-2 AS-i Master
C79000-G8976-C142/02
General Structure of the AS-i Slave Address
If an AS-i slave is addressed in a command or in a reply, the address is structured
as shown below:
Bit 7 Bit 5 Bit 4 Bit 3 Bit 0
S bit Slave address
Where the S(elect) bit for selecting the slave type is specified as follows:
S
S bit = 0
Standard AS-i slave or AS-i slave with extended addressing mode in address
area A
S
S bit = 1
AS-i slave with extended addressing mode in address area B