
Reference
MVI56E-MNETR ♦ ControlLogix Platform
User Manual
Modbus TCP/IP Interface Module with Reduced Data Block
Page 124 of 175
ProSoft Technology, Inc.
June 14, 2011
Formatted Pass-Through Command Blocks (Read Block)
Offset
Description
Length
0
9959
1
1
Number of word registers in Modbus data set
1
2
Starting word address for Modbus data set
1
3 to 21
Modbus data set
19
22 to 40
Bit mask for the data set. Each bit to be considered with the
data set will have a value of 1 in the mask. Bits to ignore in
the data set will have a value of 0 in the mask.
19
41
9959
1
Formatted Pass-Through Command Blocks (Read Block)
Offset
Description
Length
0
9970
1
1
1
1
2
0
1
3 to 40
Spare data area
38
41
9996
1
The ladder logic should copy and parse the received message and control the
processor as expected by the master device. The processor must respond to the
formatted pass-through control blocks with a write block. The following tables
describe the format of the write blocks.
Formatted Pass-Through Response (Write Block)
Offset
Description
Length
0
9956, 9957, 9958, 9960 or 9961
1
1 to 41
Spare data area
41
Formatted Pass-Through Response (Write Block)
Offset
Description
Length
0
9959
1
1 to 41
Spare data area
41
Formatted Pass-Through Response (Write Block)
Offset
Description
Length
0
9970
1
1 to 41
Spare data area
41