Omron C200H-ASC11, Manual, Page: 56 / 301

46
Opening a Communications Port
Section 4-2
4-2-3 Control/Monitor Commands for Transmission Control Signals
When control of the transmission control signals is not specified in the OPEN
command (i.e., when they are set to OFF), they can be controlled and moni-
tored using the following commands.
4-2-4 Device Symbol
The following details are specified by the device symbol (peripheral device
name).
• I/O specifications (use of the transmission/receive buffer)
• Control of transmission control signals
• Output code for the PRINT command
Note For details on the output codes for the PRINT command, refer to 4-3-1
PRINT# Command .
Action Command Example Conditions
Turn RTS signal ON/OFF RTS RTS #1_SET Only possible when RTS_ON is specified in the
OPEN command.
Turn DTR signal ON/OFF DTR DTR #1_SET Possible when the port is open.
Monitor the DSR signal DSR IF DSR(1) THEN ... None
Monitor the CTS signal CTS IF CTS(1) THEN ... None
Device
symbol
Periphera
l device
I/O (send/receive) Transmission control signals
Communications port open I/O command
execution (PRINT
or INPUT)
Reception
by ASCII
Unit (using
receive
buffer)
Transmissio
n by ASCII
Unit (using
send buffer)
RTS DTR RTS DTR
RTS_OFF
in OPEN
command
RTS_ON in
OPEN
command
Port 1/
terminal
port
Port 2 RTS_ON
and
RTS_OFF
in OPEN
command
COMU General-
purpose
communi-
cation
device Yes Yes OFF ON ON OFF ON No
change
TERM Terminal Yes Yes OFF ON ON OFF ON No
change
SCRN Display None Yes OFF ON OFF OFF ON No
change
LPRT
(See note.) Printer None Yes OFF ON OFF OFF ON No
change
NKPRT
(See note.) Printer None Yes OFF ON OFF OFF ON No
change
EKPRT
(See note.) Printer None Yes OFF ON OFF OFF ON No
change
KYBD Keyboard Yes None OFF ON ON OFF ON No
change