Emerson PACSystems RX3i - Figure 33: RTU Report Device Type Message Format

PACSystems™ RX3i and RSTi-EP CPU Reference Manual Section 6
GFK-2222AK October 2019
Serial I/O, SNP & RTU Protocols 181
6.3.3.10.6 Response:
The descriptions of the fields in the response are covered in the query description.
6.3.3.11 Message (17): Report Device Type
6.3.3.11.1 Format:
Figure 33: RTU Report Device Type Message Format
Address
Error Check
Func 17
Query
Normal Response
Address
Device
Type 43
Error Check
Func 17
Slave Run
Light
Data
Byte
Count
6.3.3.11.2 Query:
The Report Device Type query is sent by the master to a slave in order to learn what type
of programmable control or other computer it is.
▪ An Address of zero is not allowed as this cannot be a broadcast request.
▪ The Function code is 17.
6.3.3.11.3 Response:
▪ The Byte Count field is one byte in length and is equal to 5.
▪ The Device Type field is one byte in length and is equal to 43 (hexadecimal) for
PACSystems
▪ The Slave Run Light field is one byte in length. The Slave Run Light byte is equal to
OFFH if the CPU is in RUN Mode. It is equal to 0 if the CPU is not in RUN Mode.
▪ The Data field contains three bytes. For PACSystems CPUs, the first byte is the Minor
Type, and the remaining bytes are zeroes. The following table lists minor types.