Model IR400 MODBUS
2
1.1.3.2 Modbus Read Response Message
Byte
Modbus
Range
Referenced to IR400
1st
Slave Address
1-247* (Dec)
IR400 ID (Address)
2nd
Function Code
03
Read Holding Registers
3rd
Byte Count
02
No. of Data Bytes
4th
Data Hi
00-FF (Hex)
IR400 Hi Byte Status Data
5th
Data Lo
00-FF (Hex)
IR400 Lo Byte Status Data
6th
CRC Hi
00-FF (Hex)
CRC Hi Byte
7th
CRC Lo
00-FF (Hex)
CRC Lo Byte
Table 3: Modbus Read Response Message
1.1.4 Modbus Write Command Protocol (Query/Response)
1.1.4.1 Modbus Write Query Message
Byte Modbus
Range
Referenced to IR400
1st
Slave Address
1-247* (Dec) IR400 ID (Address)
2nd
Function Code
06
Preset Single Register
3rd
Register Address Hi
00
Not Used by IR400
4th
Register Address Lo
00-FF (Hex) IR400 Commands
5th
Preset Data Hi
00-FF (Hex) IR400 Hi Byte Command Data
6th
Preset Data Lo
00-FF (Hex) IR400 Lo Byte Command Data
7th
CRC Hi
00-FF (Hex) CRC Hi Byte
8th
CRC Lo
00-FF (Hex) CRC Lo Byte
Table 4: Modbus Write Query Message
•
*
NOTE:
Address 0 is reserved for broadcast mode and will not be
supported at this time.
•
**
NOTE:
Start Address can be a maximum of 9999 Address Locations
(0000-270E)
1.1.5 Modbus Write Response Message
Byte
Modbus
Range
Referenced to IR400
1st
Slave Address
1-247* (Dec)
IR400 ID (Address)
2nd
Function Code
06
Preset Single Register
3rd
Register Address Hi
00
Not Used by IR400
4th
Register Address Lo 00-FF (Hex)
IR400 Commands
5th
Preset Data Hi
00-FF (Hex)
IR400 Hi Byte Command Data
6th
Preset Data Lo
00-FF (Hex)
IR400 Lo Byte Command Data
7th
CRC Hi
00-FF (Hex)
CRC Hi Byte
8th
CRC Lo
00-FF (Hex)
CRC Lo Byte
Table 5: Modbus Write Response Message
Summary of Contents for IR400
Page 2: ......
Page 15: ...Model IR400 11 Figure 5b IR400 Mounting Dimensions with a European Box ...
Page 20: ...Model IR400 16 Figure 7 Wiring Diagram from IR400 to Control Equipment ...
Page 41: ...Model IR400 37 9 6 Engineering Documentation ...
Page 45: ...Model IR400 HART Field Device Specification for Point IR Gas Detector ...
Page 78: ...Model IR400 Infrared Point Detector for Hydrocarbon Gas Applications Modbus programming guide ...