ASMi-52 Ver. 2.5 DTE Interface Connectors A-1
Appendix A Interface Connector Specifications

A.1 DTE Interface Connectors

V.35, X.21 and RS-530 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.
The RS-530 interface terminates in a 25-pin, D-type female connector. Table A-1
lists the pin assignment of the V.35, X.21 and RS-530 interface connectors.
Table A-1. V.35, X.21 and RS-530 Connector Pinouts
V.35 RS-530 X.21 Description
34-Pin DB-25 DB-15
Signal
Function
Pin Circuit Pin Circuit Pin
Circuit
(Function)
Protective
Ground
A Frame 101 1 1
----
(Shield)
Chassis Ground. It may be
isolated from Signal Ground.
Signal
Ground
B Signal 102
GND
7 AB 8 ----
(GND)
Common signal and DC power
supply ground.
Transmitted
Data
P
S
TD(A) 103
TD(B) 103
2
14
BA(A)
BA(B)
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
3
16
BB(A)
BB(B)
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 4
19
CA(A)
CA(B)
3
10
C(A)
C(B)
(Control)
A positive level to ASMi-52
when data transmission is
required.
Clear to Send D CTS 106 5
13
CB(A)
CB(B)
A positive level from
ASMi-52 with delay, after
receipt of Request to Send, and
when ASMi-52 is ready to
transmit.