RayTek MI3 User Manual

Modbus
MI3 Rev. G Nov/2015 99
15.2 Programming
Functions codes and start addresses are listed in decimal.
15.2.1 Supported Functions
Function code
Modbus Function
Description
01
Read Coils
Read n bits
02
Read Discrete Inputs
Read n bits
03
Read Holding Registers
Read n 16 bit words
04
Read Input Registers
Read n 16 bit words
06
Write Single Register
Write a 16 bit word
16
Write Multiple Registers
Write n 16 bit words
15.2.2 Parameter Data
32 bit registers are transmitted in full Big-Endian mode, meaning most significant word is transmitted
first, least significant word is transmitted last. The byte order within a word is Big-Endian as well.
While some registers hold integer values, there are some holding floating points. The interchange
formats of the IEEE-754 standard for Floating-Point Arithmetic is used for representing floating
points.
The following table lists all parameters, its content, their formats and usage.
15.2.2.1 Box Parameter
<k> … number of output channel, depending on the number of physically installed output channels of
the Comm Box.
Items (registers, discretes or coils) are addressed starting at zero. Therefore items numbered 1-10000
are addressed as 0-9999.
Start
address
Size
[bits]
Modbus Access
Data
Type
Content
Values
MI3[M]
command
1
16
input register
short
error code for last
request
0: no error
1: value out of range
2: illegal head number
3: illegal analog output number
4: illegal output mode
5: output disabled error
99: unspecified error
-
10
64
input register
hex
Serial number
e.g. 98123
XV
20
64
input register
string
Unit identification
e.g. MI3COMM
XU
30
64
input register
string
Box Firmware Revision
e.g. 2.10
XR
40
16
input register
short
Modbus slave address
1 .. 247
XAS
50
32
input register
string
Box special
e.g. RAY, LAS
DS
60
32
holding register
integer
Baud rate RS485
9600, 19200, 38400, 57600, 115200
BR
70
16
holding register
char
Temperature Unit
0x43 ('C'), 0x46 ('F')
U
80
32
input register
float
Box Temperature
XJ
90
16
holding register
short
Switch panel lock
0: unlocked, 1: locked
J

RayTek MI3 Specifications

General

Brand	RayTek
Model	MI3
Category	Accessories
Language	English