Modbus/TCP & Modbus RTU Function Codes
January 09 UDA2182 Communications User Guide 25
8.5 Function Code 17 (11h) - Report UDA ID
Description
Function code 17 (11h) is used to report the device information such as Slave ID, device description and
firmware version.
Query
The query message specifies the function code only.
Example:
Read Device ID from a slave at address 2.
Query message format for function code 17 (11h)
Slave Address (00 for
TCP)
Function
Code
CRC (RTU) CRC (RTU)
TCP Example 00 11
RTU Example 02 11 CRC CRC
Response
The response is a record format describing the instrument.
Response message format for function code 17 (11h)
Slave
Address
Function
Code
Byte
Count
Slave
ID
Run
Indicator
Status
Device
Description
Model
ID
Device
Class
ID
Device
Mapping
CRC
(RTU)
CRC
(RTU)
Slave Address – 00 for TCP. RTU is slave address. Example: 02
Slave ID - The Slave ID number for the UDA2182 is 21 (hex).
Run Indicator Status - (one byte) (byte 4). FF=ON
Device Description - (bytes 5-20)- 16 Character ASCII Message with the following format:
‘H’ ‘C’ ‘9’ ‘5’
or
‘3’
or
‘7’
‘0’
or
‘A’
‘’ ‘‘ up to 9 character version number in
floating point notation.
zeros are appended for
the remaining bytes
For example, a UDA with version number 3.10 would have the following device description:
‘U’ ‘D’ ‘A’ ‘2’ ‘1’ ‘8’ ‘2‘ ‘ ’ ‘0’ ‘3’ ‘.’ ‘1’ ‘0’ 0 0 0
Model ID - 00 (one byte) (byte 21)
Device Class ID - The Device Classification. (one byte) (byte 22)
Class ID Class
00 Generic Class (Fixed Address Mappable)
01-FF Future
Continued