Emerson PNC001-A Series User Manual

PACSystems™ RX3i and RSTi-EP CPU Reference Manual Section 6
GFK-2222AK October 2019
Serial I/O, SNP & RTU Protocols 180
6.3.3.10.3 Response:
▪ The descriptions of the fields in the response are covered in the query description.
Note: The force multiple outputs request is not an output override command. The outputs
specified in this request are ensured to be forced to the values specified only at the beginning
of one sweep of the user logic.Message (16): Preset Multiple Registers
6.3.3.10.4 Format:
Figure 32: RTU Preset Multiple Registers Message Format
Address
Number of
Registers
Error Check
Func
16
Query
Normal Response
Address
Error Check
Func
16
Byte
Count
Data
Starting
Register No.
Number of
Registers
Starting
Point
6.3.3.10.5 Query:
▪ An Address of 0 indicates a broadcast request. All slave stations process a broadcast
re-quest and no response is sent.
▪ The value of the Function code is 16.
▪ The Starting Register Number is two bytes in length. The Starting Register Number
may be any value less than the highest register number available in the attached
CPU. It is equal to one less than the number of the first register preset by this request.
▪ The Number of Registers value is two bytes in length. It must contain a value from 1
to 125 inclusive. The sum of the Starting Register Number and the Number of
Registers value must be less than or equal to the highest register number available
in the attached CPU. The high order byte of the Starting Register Number and
Number of Registers 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.
▪ The Byte Count field is one byte in length. It is a binary number from 2 to 250
inclusive. It is equal to the number of bytes in the data field of the preset multiple
registers request. Note that the Byte Count is equal to twice the value of the Number
of Registers.
▪ The registers are returned in the Data field in order of number with the lowest
number register in the first two bytes and the highest number register in the last two
bytes of the Data field. The number of the first register in the Data field is equal to
the starting register number plus one. The high order byte is sent before the low
order byte of each register.

Emerson PNC001-A Series Specifications

General

Brand	Emerson
Model	PNC001-A Series
Category	Controller
Language	English