PM
-
3133i User
’s Manual v1.02
Last Revised: Apr. 2023 Page: 21
Copyright © ICP DAS Co., Ltd. All Rights Reserved.
E-mail: [email protected]
6.2 Modbus-RTU setting
6.2.1 Specifications
Protocol
Modbus-RTU
Transmission
Specifications
Bits per Byte
：
1 start bit
8 data bits, least significant bit sent first
None Parity
1 stop bits
Error Check
：
Cyclical Redundancy Check (CRC)
Baud Rate
9600, 19200 (Default), 38400, 115200
Modbus slave address
1-64 (Default = 1)
Modbus Function Code
：
01h, 03h, 04h, 05h, 06h, 0Fh, 10h
Code
MODBUS_ name
Description
01h
Read Coils
Read boolean values of read/write location
05h
Write Single Coil
Set one boolean value of read/write location
0Fh
Write Multiple Coil
Set boolean values of read/write location
03h
Read Holding Registers
Read the contents of read/write location
06h
Write Single Register
Set the content of one read/write location
10h
Write Multiple Registers
Set the contents of read/write location
04h
Read Input Registers
Read the contents of read only location
Note: the max. data reading of Function 03 and Function04 is 125 registers
Data format
Integer
：
16 bits with sign, each with 1 register
Unsigned Integer
：
16 bits without sign, each with 1 register
Float
：
IEEE 754 Format
，
each with 2 registers,
Low Word is first priority while transmit
