Fieldbus controller 750-842 • 57
Example of process input image
Modular I/O System
ETHERNET TCP/IP
3.2.4.1
Example of a process input image
The following figure is an example of a process input image.
The configuration comprises of 16 digital and 8 analog inputs.
The process image thus has a data length of 8 words for the analog and 1 word
for the digital inputs, i.e. 9 words in total.
Bit 1
Bit 4
Word2
Word1
Word2
Word1
Word2
Word1
Word2
Word1
Word2
Word1
Word2
Word1
1
4
1
4
1
1
4
1
ON
LINK
TxD/RxD
ERROR
Ethernet
750-842
I/O
WA
G
O
ß
I/
O
ß
SY
ST
E
M
DI DI
DI
DI
AI AI
AI
AI
Word2
Word1
Word2
Word2
Word1
Highbyte
Lowbyte
0x0003 %IW3
0x0002 %IW2
0x0001 %IW1
0x0000 %IW0
0x0005 %IW5
0x0004 %IW4
0x0007 %IW7
0x0006 %IW6
0x0008 %IW8
0x0001 %IX8.1
0x0000 %IX8.0
0x0003 %IX8.3
0x0002 %IX8.2
0x0004 %IX8.4
0x0004 %IX8.4
0x0008 %IX8.8
0x000C %IX8.12
0x0005 %IX8.5
0x0005 %IX8.5
0x0009 %IX8.9
0x000D %IX8.13
0x0006 %IX8.6
0x0006 %IX8.6
0x000A %IX8.10
0x000E %IX8.14
0x0007 %IX8.7
0x0007 %IX8.7
0x000B %IX8.11
0x000F %IX8.15
Process input image
(Word)
addresses
Process input image
(Bit)
Input modules
750- 402 402
472
472 402 476
402 476
DI: Digital Input
AI:Analog Input
addresses
MODBUS PFC
MODBUS PFC
Fig. 3-24: Example of a process input image
G012924e