Rtu Message Descriptions; Figure 23: Rtu Read Output Table Message Format - Emerson PACSystems RX3i User Manual

PACSystems™ RX3i and RSTi-EP CPU Reference Manual
GFK-2222AK
18-21
22 Mask Write 4x Registers
23 Read/Write 4x Registers
24–66
67 Read Scratch Pad
68-127
128-255
6.3.3

RTU Message Descriptions

This section presents the format and fields for each RTU message.
6.3.3.1 Message (01): Read Output Table
6.3.3.1.1 Format:

Figure 23: RTU Read Output Table Message Format

6.3.3.1.2 Query:
An address of 0 is not allowed because this cannot be a broadcast request.
▪
▪
Serial I/O, SNP & RTU Protocols
Address
Func
01
Address
Func
01
The function code is 01.
The starting point number is two bytes in length and may be any value less than the
highest output point number available in the attached CPU. The starting point
number is equal to one less than the number of the first output point returned in the
normal response to this request.
Not Defined
8
13+byte 11
76
Not Defined
6
Not Defined
Not Defined
Starting Number of
Point No. Points
Hi Lo Hi Lo
Query
Data
Byte
Count
Normal Response
Section 6
October 2019
Not Defined
8
5+byte 3
76
Not Defined
3 + 3rd byte
76
Not Defined
3
Error
Check
Error
Check
170