Access to the Data of the AS-i Slaves

3.2.2Access to the AS-i Analog Data

Data Access with STEP 7 Micro

You access the analog data of the AS-i slaves using the analog commands of the ªSTEP 7 Micro/WIN32º programming language.

Example

The following example shown in STL is valid for a CPU 222 with a CP 243-2 plugged in directly beside it. The program reads the analog input value of slave 3 (channel 2) cyclically and sends it to the analog output slave 16 (channel 1).

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 4

//Then : process AS-i analog values

SBR 4 (STL)

NETWORK 1

 

LD

SM0.0

//Always 1

RI

Q1.0,6

//Select bank 33

SI

Q1.5,1

//Select bank 33

SI

Q1.0,1

//Select bank 33

MOVW AIW10, VW50

//Read slave 4, channel 2

RI

Q1.0,1

//Select bank 40

SI

Q1.3,1

//Select bank 40

MOVW VW50, AOW0

//Write slave 17, channel 1

RI

Q1.0,6

//Important: deselect the analog bank

SIMATIC NET CP 243-2 AS-i Master

3-15

C79000-G8976-C142/02

Page 63
Image 63
Siemens CP 243-2 installation instructions Access to the AS-i Analog Data, SBR 4 STL