Appendix A - Interface Connections

AM64/128A User Manual

 

 

V.35 (MRAC) Connector Pin allocation

Note: Circuit 108/1 is not available on the connector as an interface line but is software clamped in the ON state.

 

Pin

 

 

 

TYPE

Unbal

A wire

B wire

Circuit

Description

SITS 89/43

 

 

 

 

 

 

B

 

 

102

Common Return

Common

 

P

S

103

Transmitted Data

Load

 

R

T

104

Received Data

Generator

C

 

 

105

Request to Send

Load

D

 

 

106

Ready for Sending

Generator

E

 

 

107

Data Set Ready

Generator

F

 

 

109

Data Channel Received

Generator

 

U

W

113

External Transmitter Signal Element Timing

Load

 

Y

AA*

114

Transmitter Signal Element Timing

Generator

 

V

X

115

Receiver Signal Element Timing

Generator

N

 

 

140

Remote Loopback

Load

L

 

 

141

Local Loopback

Load

NN*

 

 

142

Test Indicator

Generator

 

 

 

 

 

 

Note that on some MRAC connectors pin ‘AA’ is marked as ‘a’ and pin ‘NN’ is marked ‘m’.

37 Way D-type V.36 Connector pin allocation

 

Pin

 

 

 

TYPE

Unbal

A wire

B wire

Circuit

Description

SITS 89/43

 

 

 

 

 

 

19, 20, 27, 29, 31

102

Common Return

Common

 

 

 

103

 

 

 

4

22

Transmitted Data

Load

 

6

24

104

Received Data

Generator

 

7

25

105*

Request to Send

Load

9

(9)

(27)

106*

Ready for Sending

Generator

11

(11)

(29)

107*

Data Set Ready

Generator

13

(13)

(31)

109*

Data Channel Received

Generator

 

17

35

113

External Transmitter Signal Element Timing

Load

 

5

23

114

Transmitter Signal Element Timing

Generator

 

8

26

115

Receiver Signal Element Timing

Generator

14

 

 

140

Remote Loopback

Load

10

 

 

141

Local Loopback

Load

18

 

 

142

Test Indicator

Generator

 

 

 

 

 

 

*Standards indicate that the control circuits 105,106,107,109 may be implemented as balanced circuits (using both A and B wires) or unbalanced single ended circuits. In the case of the control circuits the A wire is to be used and the B wire is to be joined to GND (circuit 102) at the receiver end of the circuit. In the AM64/128A circuit 105 is implemented as a balanced circuit and 106,107,109 are unbalanced.

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Image 41
American Telecom AM64/128A manual Mrac Connector Pin allocation, Way D-type V.36 Connector pin allocation