Connection With General-Purpose Serial Communications Devices; Overview - Omron NX-series User Manual

4-5 Connection with General-purpose
Serial Communications Devices
The following describes data exchange between the CPU Unit and general-purpose serial communica-
tions devices.
4-5-1

Overview

The NX1P2 CPU Unit can exchange data with general-purpose serial communications devices by
using the instructions to send and receive data in No-Protocol mode.
To use this function, you mount a Serial Communications Option Board on the NX1P2 CPU Unit, set its
Serial communications mode to No-Protocol, and connect their serial ports together.
NX1P2 CPU Unit
RS-232C or
RS-422A/485
The instruction to send data in No-Protocol mode refers to an instruction to output the specified data
from the specified serial port without converting it.
The instruction to receive data in No-Protocol mode refers to an instruction that reads data received at
the specified port into the specified variable without converting it.
Refer to the NJ/NX-series Instructions Reference Manual (Cat. No. W502-E1-17 or later) for the speci-
fication of instructions.
Additional Information
To enable the CPU Unit to exchange data with general-purpose serial communications devices
by using the instructions to send and receive data in No-Protocol mode, you must program the
communications procedure (protocol) for the remote device.
For example, program the sequence processing and retry processing between the command
and the response, data type conversion processing, branching processing, and other process-
ing steps to be performed based on the communications protocol of the remote device.
NX-series NX1P2 CPU Unit Built-in I/O and Option Board User's Manual (W579)
RS-232C or RS-422A/485 Option Board
User program
NX_SerialSend instruction
NX_SerialRcv instruction
Sending and receiving data
General-purpose serial communications device
(Barcode reader etc.)
4 Serial Communications
4
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