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 138
6.1.6 Example COMMREQ Command Blocks for Serial Port
Setup function
The following COMMREQ command blocks provide examples for configuring the various
protocols. All values are in decimal unless followed by an H indicating hexadecimal.
Note that an example is not provided for Message Mode, but it can be setup with a
command block similar to the one for Serial I/O, with a value of 7 for the protocol
selector.
6.1.7 Example COMMREQ Command Block for Configuring
SNP Protocol
Values
Meaning
Address
16
Data Block Length
Address + 1
0 = No Wait (WAIT mode not supported)
WAIT/NOWAIT Flag
Address + 2
0008 = %R, register memory
Status Word Pointer Memory
Type
Address + 3
Zero-based number that gives the address of the
COMMREQ status word (for example, a value of 99 gives
an address of 100 for the status word)
Status Word Pointer Offset
Address + 4
not used
Idle Timeout Value
Address + 5
not used
Maximum Communication
Time
Address + 6
FFF0H
Command Word (serial port
setup)
Address + 7
1 = SNP
Protocol
Address + 8
0 = Slave
Port Mode
Address + 9
See COMMREQ Command Block Parameter Values.
Data Rate
Address + 10
0 = None, 1 = Odd, 2 = Even
Parity
Address + 11
not used (SNP always chooses NONE by default)
Flow Control
Address + 12
0 = None, 1 = 10ms, 2 = 100ms, 3 = 500ms
Turnaround Delay
Address + 13
0 = Long, 1 = Medium, 2 = Short, 3 = None
Timeout
Address + 14
not used (SNP always chooses 8 bits by default)
Bits Per Character
Address + 15
0 = 1 Stop Bit, 1 = 2 Stop bits
Stop Bits
Address + 16
not used
Interface
Address + 17
not used (SNP always chooses 4-wire mode by default)
Duplex Mode
Address + 18
user-provided
72
Device identifier bytes 1 and 2
Address + 19
user-provided
72
Device identifier bytes 3 and 4
Address + 20
user-provided
72
Device identifier bytes 5 and 6
Address + 21
user-provided
72
Device identifier bytes 7 and 8
72
The device identifier for SNP Slave ports is packed into words with the least significant character in the least significant byte of the word. For
example, if the first two characters are “A” and “B,” the Address + 18 will contain the hex value 4241.

Emerson PNC001-A Series Specifications

General

Brand	Emerson
Model	PNC001-A Series
Category	Controller
Language	English