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X.21 DTE Cable
Connection
An X.21 DTE cable is connected as follows:
- The X1 connector (DB28) is connected to the SA interface card of a router.
- Connection of the X2 connector (DB15) depends on the type of the WAN link:
- If the WAN link is a digital data network (DDN) line, connect the X2 connector to an interface of a channel service unit (CSU) or data service unit (DSU).
- If the WAN link is a dial-up line, connect the X2 connector to the serial interface on a modem.
Appearance and Structure
Figure 7-34 Structure of the X.21 DTE Cable
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Pin Assignments
Table 7-58 lists the pin assignments of an X.21 DTE cable.
Technical Specifications
Table 7-59 Technical specifications of the X.21 DTE Cable
| Item | Details |
|---|---|
| Part Number | 04043593 |
| Model | SS-DL-X21-DTE-3 |
| Description | Single Cable, X.21 Serial Port Cable, 3m, D15M, CC(5P+8C)0.32P296U(S), D28M, DTE |
| Cable length [m] | 3 m |
| Connector type X1 | D28M |
| Connector type X2 | D15F |
Before selecting SA cables for a router, obtain the remote device type (including the synchronous/asynchronous mode and DTE/DCE role), and the signal standard, baud rate, and clock required for the remote device.