Siemens SIMATIC NET CP 343-2, Руководство пользователя

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4 Data Exchange between User Program and AS−i Slaves
41
CP 343−2 / CP 343−2 P AS−Interface Master
Release 08/2008
C79000−G8976−C149−04
Example of a Configuration
Figure 2−2 shows an example of the PLC CPU addressing 4 standard or A slaves.
The base addresses m = 256 for the I/O data are configured in STEP 7.
The bits relevant for the user program are shown on a gray background. The bits
shown on a white background are irrelevant for the user program since no AS-i
slave bits are assigned here.
DP master
16
Input bytes
0
4
5 6
7
0
1
2 3 4
5 6 7
1
.
.
.
271
.
.
.
4 I module
Slave no. 2 Slave no. 3 Slave no. 4 Slave no. 31
AS-i slaves
4 I module 4 I/4 O module 2 I/2 O module 4 O module
258
271
256
256
257
258
slave 1
slave 1
slave 2
slave 3
slave 30
slave 4
slave 5
slave 2 slave 3
slave 4
slave 5
slave 30 slave 31
Bit 0 Bit 1 Bit 2
Bit 3
Bit 0
Bit 0
Bit 0
Bit 0
Bit 0
Bit 0
Bit 0 Bit 0
Bit 0
Bit 0
Bit 0
Bit 0
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 1
Bit 3
Bit 2
Bit 2 Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 2
Bit 3
Bit 3
Bit 3
Bit 3
Bit 3
Bit 3
Bit 2
Bit 3
Bit 3
Bit 3
Bit 3 Bit 3
Bit 3 Bit 1 Bit 0
Bit 1 Bit 0
Output bytes
16
Bit 2
slave 31
Bit 0 Bit 1 Bit 3
257
7 6 5 4
3 2 1 0
Figure 4-2
In the figure above, for example, the 2I/2O module (AS-i slave number 3 with two
inputs and two outputs) occupies bits 0 and 1 in input byte 1 and bits 2 and 3 in
output byte 1.
The assignment of the AS-i terminals of the AS-i bus modules to the data bits of
the input/output bytes is shown below based on the example of slave number 3:
1 0 Bit no.
Input byte 1
Terminal 1 on AS-i bus module
Terminal 2 on AS-i bus module
3 2 Bit no.
Output byte 1
Terminal 3 on AS-i bus module
Terminal 4 on AS-i bus module