Siemens CP 243-2 User Manual

Access to the Data of the AS-i Slaves

3-7

SIMATIC NET CP 243-2 AS-i Master
C79000-G8976-C142/02

3.1.2

Access to the AS-i User Data

Data Access with STEP 7 Micro

To access the binary data of the slaves, you use the analog transfer commands of
the STEP 7 Micro/WIN32 programming language.

Example

If you want to access individual bits of the slave data, you can use the method
shown in the following sample program.

The example created with STEP 7 Micro/WIN32 is valid for a CPU 222 with a
CP 243-2 plugged in directly beside it:

OB1 (STL)

NETWORK 1
LD SM0.1

//If: bit “First Scan”:

SI Q1.7, 1

//PLC_RUN = 1

LD I1.1

//If: CP 243-2_READY

CALL 1

//Then: AS-i I/O processing (standard or A slaves)

SBR 1 (STL)

NETWORK 1
LD SM0.0

//Always 1

RI Q1.0,6

//Select bank 0

BMW AIW0, VW100, 8

//Transfer standard slaves

SI Q1.0,5

//Select bank 31

BMW AIW0, VW116, 8

//Transfer B slaves

//Below, several examples of access to AS-i bits
LD V100.0

//If bit 1 of slave 1

A V115.1

//And bit 2 of slave 31

A V116.0

//And bit 1 of slave 1B

= V203.2

//The bit 3 of slave 7 = 1

LD SM0.0