Modbus/TCP & Modbus RTU Function Codes
Function Code 17 (11h) - Report HC900 ID
38 HC900 Process Controller Communications User Guide Revision 13
April 2017
4.11 Function Code 17 (11h) - Report HC900 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)
Response
The response is a record format describing the instrument.
Response message format for function code 17 (11h)
Slave Address – 00 for TCP. RTU is slave address. Example: 02
Slave ID - The Slave ID number for the HC930 is 93 (hex). For the HC950 it is 95 (hex) (one byte) (byte
3). For HC970 it is 70 (hex). For HC970R it is 7A (hex).
Run Indicator Status - (one byte) (byte 4). 00=OFF; FF=ON
Device Description - (bytes 5-20)- 16 Character ASCII Message with the following format:
up to 9 character version number in
floating point notation.
zeros are appended for
the remaining bytes
For example, an HC950 with version number 2.000 would have the following device description:
Model ID - 00 (one byte) (byte 21)
Device Class ID - The Device Classification. (one byte) (byte 22)
Generic Class (Fixed Address Mappable)
Continued