6.2 List of MODBUS TCP Supported Commands
6.2 List of MODBUS TCP Supported Commands
6.2.1 List of MODBUS Function Codes
Table of supported commands
Code Name (MODBUS) Name
Remarks
FP7 supported
01 Read Coil Status Read Y and R Coils
0X ●
02 Read Input Status Read X Input 1X ●
03 Read Holding Registers Read DT 4X ●
04 Read Input Registers Read WL and LD
3X ●
05 Force Single Coil Write Single Y and R 0X ●
06 Preset Single Register Write DT 1 Word 4X ●
08 Diagnostics Loopback Test
- -
15 Force Multiple Coils Write Multiple Y's and R's 0X ●
16 Preset Multiple Registers Write DT Multiple Words 4X ●
22 Mask Write 4X Register Write DT Mask
4X -
23 Read/Write 4X Registers Read/Write DT 4X -
(Note 1) Types of MODBUS function codes vary by commands to be used.
Table for MODBUS reference No. and device No.
Data on BUS
(hexadecimal)
Coil
000001-002048 0000-07FF Y0-Y127F
002049-034816 0800-87FF R0-R2047F
Input 100001-108192 0000-1FFF X0-X511F
Holding register 400001-465536 0000-FFFF DT0-DT65535
Input register
300001-301024 0000-03FF WL0-WL1023
302001-318384 07D0-47CF LD0-LD16383
(Note 1) The table above indicates correspondence between the MODBUS reference numbers for accessing from a
higher device to FP7 using the MODBUS protocol, and the operation device numbers of FP7.
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