Specifications

DTE Interface Connectors A-1
Appendix A
Interface Connector
Specifications
A.1 DTE Interface Connectors
V.35 and X.21 Interface Connectors
The V.35 interface of the ASMi-52 modem terminates in a 34-pin female
connector. The X.21 interface terminates in a 15-pin, D-type female connector.
Table A-1 lists the pin assignment of the V.35 and X.21 interface connectors.
Table A-1. V.35 and X.21 Connector Pinouts
V.35 X.21 Description
34-Pin
DB-15
Signal
Function
Pin Circuit Pin Circuit
(Function)
Protective
Ground
A Frame 101 1 ----
(Shield)
Chassis Ground. It may be isolated from Signal
Ground.
Signal Ground B Signal 102
GND
8 ----
(GND)
Common signal and DC power supply ground.
Transmitted
Data
P
S
TD(A) 103
TD(B) 103
2
9
T(A)
T(B)
(Transmit)
Serial digital data from DTE. In sync applications,
the data translations must occur on the rising
edge of the transmit clock.
Received Data R
T
RD(A) 104
RD(B) 104
4
11
R(A)
R(B)
(Receive)
Serial output from the modem receiver. In sync
applications, the data translations occur on the
rising edge of the clock.
Request to Send C RTS 105 3
10
C(A)
C(B)
(Control)
A positive level to ASMi-52 when data
transmission is desired.
Clear to Send D CTS 106 A positive level from ASMi-52 with delay, after
receipt of Request to Send, and when ASMi-52 is
ready to transmit.
Data Set Ready
E
DSR 107 A positive level from ASMi-52 when power is on,
and ASMi-52 is (a) not in DIGITAL LOOP mode,
or (b) has not received a REMOTE LOOPBACK
signal from the remote unit.