Technical data

The Master Mode – Commands, Sequence, Programming
4-10
SIMATIC NET AS-Interface – Introduction and Basic Information
C79000-G8976-C089/03
4.2.2 Interface Functions
To control the master/slave interaction from the user program, there are various
functions available on the interface. The possibilities are explained based on the
illustration below. Here, simply the possible operations and the direction of data
flow are illustrated.
AS-i master AS-i slave
User
program
Process image
I/O data
CPU
CP
I/O data
Parameter
s
Configuration data
Act. params.
Act. configuration
data
LDS
LAS
Data images
Config. data
(EEPROM)
Parameters
LAS
Exp. configuration
data
1. read/write
2.
Read / store
configuration
data
3.
Configure actual
4. Supply slaves with
configured parameters
(activation)
I/O data
Figure 4-4
1. Read/write
When writing, parameters are transferred to the slave and the parameter
images on the CP; when reading, parameters are transferred from the slave or
from the CP parameter image to the CPU.
2. Read and store (configured) configuration data
Configured parameters or configuration data are read from the non-volatile
memory of the CP.
3. Configure actual
When reading, the parameters and configuration data are read from the slave
and stored permanently on the CP. When writing, parameters and configuration
data are stored permanently on the CP.
4. Supply slaves with configured parameters
Configured parameters are transferred from the non-volatile area of the CP to
the slaves.