Figure 27: Rtu Force Single Output Message Format - Emerson PACSystems RX3i User Manual

PACSystems™ RX3i and RSTi-EP CPU Reference Manual
GFK-2222AK
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6.3.3.4.3 Response:
The Byte Count is a binary number from 2 to 250 inclusive. It is the number of bytes in the
normal response following the byte count and preceding the error check. Note that the
Byte Count is equal to two times the number of analog inputs returned in the response. A
maximum of 250 bytes (125) analog inputs is set so that the entire response can fit into
one 256-byte data block.
The analog inputs are returned in the Data field in order of number with the lowest
number analog input in the first two bytes and the highest number analog input in the
last two bytes of the Data field. The number of the First Analog Input in the Data field is
equal to the Starting analog input number plus one. The high order byte is sent before the
low order byte of each analog input.
6.3.3.5 Message (05): Force Single Output
6.3.3.5.1 Format:

Figure 27: RTU Force Single Output Message Format

6.3.3.5.2 Query:
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Serial I/O, SNP & RTU Protocols
The Number Of Analog Inputs value is two bytes in length. It must contain a value
from 1 to 125 inclusive. The sum of the Starting Analog Input value and the Number
Of Analog Inputs value must be less than or equal to the highest analog input
number available in the at-attached CPU. The high order byte of the Starting Analog
Input Number and Number of Analog Inputs fields is sent as the first byte in each of
these fields. The low order byte is the second byte in each of these fields.
Address
Address
An Address of 0 indicates a broadcast request. All slave stations process a broadcast
re-quest and no response is sent.
The function code is equal to 05.
Func
Point
05
Number
Hi Lo Hi
Query
Func
Point
05
Number
Hi Lo Hi
Normal Response
Error Check
Data
00H
Lo
Error Check
Data
00H
Lo
Section 6
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