Modbus Register Mapping; Table 124: Register Access Reading (With Fc3, Fc4 And Fc23) - WAGO -I/O-SYSTEM 750 Manual

244 Fieldbus Communication
12.2.4

MODBUS Register Mapping

The following tables display the MODBUS addressing and the corresponding
IEC61131 addressing for the process image, the PFC variables, the NOVRAM
data, and the internal variables is represented.
Via the register services the states of the complex and digital I/O modules can be
determined or changed.
Register Access Reading (with FC3, FC4 and FC23)

Table 124: Register access reading (with FC3, FC4 and FC23)

MODBUS address
[dec]
0...255
256...511
512...767
768...1023
1024...4095
4096...12287
12288...24575 0x3000...0x5FFF
24576...25340 0x6000...0x62FC
25341...28671 0x62FD...0x6FFF
28672...29435 0x7000...0x72FB
29436...32767 0x72FC...0x7FFF
32768...36863 0x8000...0x8FFF
36864...65535 0x9000...0xFFFF
Manual
1.5.0
750-882 Media Redundancy ETHERNET Controller
IEC 61131
[hex] address
0x0000...0x00FF %IW0...%IW255
0x0100...0x01FF %QW256...%QW511
0x0200...0x02FF %QW0...%QW255
0x0300...0x03FF %IW256...%IW511
0x0400...0x0FFF
0x1000...0x2FFF
%MW0...%MW12287
%IW512...%IW1275
%QW512...%QW1275 Physical output area (2)
WAGO-I/O-SYSTEM 750
Memory range
Physical input area (1)
First 256 words of physical input data
PFC OUT area
Volatile PFC output variables
Physical output area (1)
First 256 words of physical output data
PFC IN area
Volatile PFC input variables
- MODBUS exception:
"Illegal data address"
- Configuration register (see following
chapter "Configuration Functions")
Not with FC23!
NOVRAM
24 kB retain memory *)
*) In Target settings RETAIN on 0, flags on
MAX (24 kB)
Physical input area (2)
Additional 764 words physical input data
- MODBUS exception:
"Illegal data address"
Additional 764 words physical output data
- MODBUS exception:
"Illegal data address"
- NOVRAM
"8 kB retain memory *)
*) In Target settings RETAIN on 0, flags on
MAX (32 kB)
- MODBUS exception:
"Illegal data address"