Null-Modem Cable Configuration - Black Box Series 5000 Reference Manual

V.35 Null-Modem Cable Configuration
DB25 MALE
1
Protective GND
9
Transmitted Data (A)
10
Transmitted Data (B)
11
Received Data (A)
12
Received Data (B)
18
Transmitter Signal Element Timing (A)
19
Transmitter Signal Element Timing (B)
14
Receiver Signal Element Timing (A)
16
Receiver Signal Element Timing (B)
23
Transmitter Signal Element Timing (A)
25
Transmitter Signal Element Timing (B)
20
Data Terminal Ready
8
Data Channel Received Line Signal Detector (CD)
7
Signal Ground
4
Request to Send
6
Data Set Ready
The connecting cable must be a shielded cable.
Circuits which are paired (contain an (A) and (B) reference) should be connected to twisted pairs
within the connecting cable.
This cable is needed when it is necessary to connect two units back-to-back and a set of
modems is not available. Note that this cable specifies DB25 connectors on each end to allow
direct connection to the link interface connector on each unit.
The link speed must be defined for each of the two units.
Transmitter Signal Element Timing (A)
Transmitter Signal Element Timing (B)
Transmitter Signal Element Timing (A)
Transmitter Signal Element Timing (B)
Data Channel Received Line Signal Detector (CD)
Figure 3 - 12 V.35 Null-Modem Cable
39
Link Interfaces Reference
Protective GND
Received Data (A)
Received Data (B)
Transmitted Data (A)
Transmitted Data (B)
Receiver Signal Element Timing (A)
Receiver Signal Element Timing (B)
Data Terminal Ready
Signal Ground
Data Set Ready
Request to Send
DB25 MALE
1
11
12
9
10
14
16
23
25
18
19
8
20
7
6
4