Siemens SIMATIC NET CP 243-2, Manual

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Interface to the User Program in the S7-200 CPU
2-7
SIMATIC NET CP 243-2 AS-i Master
C79000-G8976-C142/02
2.3 Meaning of the Data in the Digital Module
Overview
The digital module of the CP 243-2 consists of four registers:
Identification register, 8 bits (I/O module identifier)
Error register, 8 bits
Input register 8DI (status byte of the CP 243-2)
Output register 8DO (control byte of the CP 243-2)
Essentially, the functions shown in the following diagram are handled via these
registers:
CP 243-2
User program
Digital module (8DI/8DO)
Analog module (8AI/8AO)
S7-200 CPU
ÍÍ
ÍÍ
ÍÍ
ÍÍ
ÍÍ
ÍÍ
ÎÎ
ÎÎ
ÎÎ
ÎÎ
ÎÎ
ÎÎ
AS-i master
AS-i cable
Status/error information
Control of the CP
Bank selection
Figure 2-2