No-Protocol Communications System - Omron CJ2 CPU UNIT SOFTWARE User Manual

Additional Information
Host Link master functions can be performed by sending the CMND(490) instruction via the
Serial Gateway when using Serial Communications Units with unit version 1.2 or later.
PLC (Host Link Master)
Serial Communications
Board/Unit

No-protocol Communications System

No-protocol communications allow simple data transmissions, such as inputting bar code data and out-
putting printer data using communications port I/O instructions. The start and completion codes can be
set, and RS and CS signal control is also possible with no-protocol communications.
The following figure shows the usage of each communications port I/O instruction, based on the com-
munications port being used and the direction of the data transfer (sending or receiving).
CPU
RS-232C
RXD
TXD
*1 Set pin 5 of the DIP switch on the front panel of the CPU Unit to OFF, and set the serial communications mode
in the PLC Setup to no-protocol communications.
*2 No-protocol communications are supported for Serial Communications Units with unit version 1.2 or later only.
CJ2 CPU Unit Software User's Manual
CMND(490)
Serial FINS
Gateway
FINS
Host Link
Host Link
terminator
header
SCU
RXDU/DRXDU
TXDU/DTXDU
General-purpose
external device
General-purpose
external device
11 Programming Devices and Communications
FINS command sent
PLC (Host Link slave)
Applicable port
CPU Unit
Serial
Communications Unit
USB port RS-232C port
No Yes
*1
Yes
*2
11-17
11