V.24 Interface; The Interface Lines Have The Following Significance - Devolo MicroLlink User Manual

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AT commands: Detailed description
3.3.1

V.24 interface

The interface between the MicroLink ISDN i and the computer consists of a
variety of data, control and signaling lines. The condition of most of the inter-
face lines is displayed by LEDs on the front of the unit.
The pin assignment of the V.24 interface for 9-pin or 25-pin connectors is as
follows:
9-pin
U*
5
3
2
6
8
9
1
47
The designations in the table name the functions of the lines (e.g. transmis-
sion data) as related to the data terminal (computer).
3.3.2

The interface lines have the following significance:

Computer/terminal operational – DTR = Data Terminal Ready
The effect of this control line on the MicroLink ISDN i is determined by the
command AT&D.
Switch on transmission – RTS = Request To Send
Operational – DSR = Data Set Ready
This signal line is normally always active (ON), but is influenced by the com-
mands AT\D and AT&S.
Clear to send – CTS = Clear To Send
This output is normally always active (ON), but is influenced by the com-
mands AT\D, AT\Q and AT&R.
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devolo MicroLink ISDN i
|
25-pin DIN ITU-T
1 E1 101
7 E2 102
2 D1 103
3 D2 104
6 M1 107
5 M2 106
22 M3 125
8 M5 109
20 S1 108
4 S2 105
* U = Housing/shield
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USA Designation (USA)
GND Protective Ground
GND Signal Ground
TxD Transmit Data
RxD Receive Data
DSR Data Set Ready
CTS Clear to Send
RI Ring Indicator
DCD Data Carrier Detect
DTR Data Terminal Ready
RTS Request to Send