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 145
6.2.5.1 COMMREQS that Must Complete Execution
■ Autodial (4400)
■ Initialize Port (4300)
■ Set Up Input Buffer (4301)
■ Flush Input buffer (4302)
■ Read port status (4303)
■ Write port control (4304)
■ Cancel Operation (4399)
■ Serial Port Setup (FFF0)
6.2.5.2 COMMREQs that can be Pending While Others Execute
The table below shows whether Write Bytes, Read Bytes and Read String COMMREQs can
be pending when other COMMREQs are executed.
NEW COMMREQ
Currently-Pending
COMMREQs
Autodial
(4400)
Write
Bytes
(4401)
Initialize Port
(4300)
Set Up Input
Buffer
(4301)
Flush Input
Buffer
(4302)
Read
Port
Status
(4303)
Write
Port
Control
(4304
)
Read
Bytes
(4402)
Read String
(4403)
Cancel
Operation
(4399)
Serial Port
Setup (FFF0)
Write Bytes
(4401)
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Read Bytes
(4402)
No
Yes
Yes
No
No
Yes
Yes
No
No
Yes
No
Read String
(4403)
No
Yes
Yes
No
No
Yes
Yes
No
No
Yes
No
6.2.6 Initialize Port Function (4300)
This function causes a reset command to be sent to the specified port. It also cancels any
COMMREQ currently in progress and flushes the internal input buffer. RTS and DTR are set
to inactive.

Emerson PNC001-A Series Specifications

General

Brand	Emerson
Model	PNC001-A Series
Category	Controller
Language	English