Access to the Data of the AS-i Slaves

3.1.2Access 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 ªFirst Scanº:

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

//Always 1

RI

Q1.0,6

//Select bank 0

BMW

VW900, AOW0, 8

//Transfer standard slaves

SI

Q1.0,5

//Select bank 31

BMW

AIW0, AOW0, 8

//Transfer B slaves

SIMATIC NET CP 243-2 AS-i Master

3-7

C79000-G8976-C142/02

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Siemens CP 243-2 installation instructions Access to the AS-i User Data, Data Access with Micro