Control the RS(RTS) and ER(DTR) signals with the system that includes the C24.
Controlling the RS(RTS) and ER(DTR) signals by the user may cause data
communication errors.
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REMARKS
(1) Confirmation of RS-232 control signal status
Each status of the control signals, ER(DTR), DR(DSR), RS(RTS) and
CD(DCD) can be confirmed in RS-232 control signal status (address:
254
/264
).
H
H
Bit position
b0
b1
b2
b3
b4
b5
b6 to b15
(2) Designation of RS and DTR signal status
Normally, the ON/OFF status of the RS(RTS) or ER(DTR) signal is set by the
C24.
To specify the ON/OFF status of the RS(RTS) or ER(DTR) signal, turn
ON/OFF the corresponding bit of the RS or DTR signal status designation
(address: 92
/132
H
1 The RS(RTS) signal is controlled by the C24 in the following cases. (Ignore setting contents.)
• When data are communicated with half-duplex communication
• When communication time and the RS and CS signals are controlled by the modem function
2 The ER(DTR) signal is controlled by the C24 in the following cases. (Ignore setting contents.)
• When the DTR and DSR signals are controlled
• When data are communicated by the modem function
3 After writing data to the buffer memory, a lag of 0 to 20ms occurs until they are reflected in the
signal.
4 When a functional protocol, RS/DTR signal status specification (protocol No. 204 to 207), is
executed with the CPRTCL instruction, the corresponding bit of the RS/DTR signal status
specification (address: 92
For details of the functional protocol, refer to Section 12.3.1.
POINT
Buffer memory address
CH1 side
CH2 side
254
264
H
RS(RTS)
DR(DSR)
ER(DTR)
CD(DCD)
CS (CTS)
CI(RI)
—
1
2
3
4
).
H
/132
) turns on or off.
H
H
6 SETTING AND WIRING
H
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