Mitsubishi Electric QJ71C24N User Manual page 65

3 SPECIFICATIONS
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4) ER(DTR) signal (4)
• When communicating data using the non procedure protocol, the Q series
C24 turns on or off (on when data is receivable) depending on the amount
of unused memory in the OS area allocated for receive data storage, if
DTR/DSR control is being performed.
Read the receive data from the sequence program, as the receive data is
stored in the OS area when the ER(DTR) signal is OFF.
If DTR/DSR control is not implemented, the ER(DTR) signal is always ON.
• If an MC protocol or bidirectional protocol is performing data
communication, the Q series C24 turns ON when communications is
enabled.
5) DR(DSR) signal (6)
• During DTR/DSR control, if this signal is OFF, the Q series C24 does not
send data to the external device.
Be sure that this signal is always turned ON when the external device is
ready to receive.
• If DTR/DSR control is not implemented, the DR(DSR) signal status is
ignored.
6) RS(RTS) signal (7)
• The Q series C24 turns ON/OFF the RS(RTS) signal as described below.
• When the communication system is full-duplex communications, if the Q
series C24 ready (X1E) is ON, the Q series C24 turns ON the RS(RTS)
signal.
• When the communication system is half-duplex communications, when the
Q series C24 sends data to an external device, it turns ON the RS(RTS)
signal.
• The RS(RTS) signal is not turned OFF even when the receive data cannot
be stored in the Q series C24.
7) CS(CTS) signal (8)
• The Q series C24 does not send data to an external device when this
signal is OFF.
• Be sure that this signal is always turned ON when the external device is
ready to receive.
8) CI(RI) signal (9)
• The CI(RI) signal is used when the modem status is monitored on the Q
series C24 side. It should be connected as needed. The CI(RI) signal is not
needed to be connected when the modem is not connected.
(2) The ON and OFF states of each signal indicate the following conditions:
(Output side)
ON ......... 5 V DC to 15 V DC,
OFF ......... –15 V DC to –5 V DC,
(3) Interface connector
Connectors of 9-pin D-sub (female) screw type (mating screw M2.6) are used as
RS-232 interface connectors for the Q series C24.
For the relevant models, refer to Appendix 6.1.
(Input side)
3 V DC to 15 V DC
–15 V DC to –3 V DC
MELSEC-Q
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