T1 Lines

In DSX-80/160, provides for connection to advanced digital lines and simplifies installation.
Additional Feature Information
Primary Rate Interface (PRI)
Direct Inward Dialing
Programming for this Feature
Programming PRI Basics
Programming Incoming Calling Party Number and Name
Programming Outgoing Calling Party Number (CPN)
Programming T1 Lines
Programming Outside Line Type, Access, and Ringing
Programming Caller ID


T1 lines require a unique T1 PCB (P/N 80061) and give the system a maximum of 24 lines in a single PCB slot. The available T1 line types include:
  • Loop Start (DTMF and Dial Pulse)
  • Ground Start (DTMF and Dial Pulse)
  • Direct Inward Dial (DID) Wink Start (DTMF and Dial Pulse)
  • Direct Inward Dial (DID) Immediate Start (DTMF and Dial Pulse)
  • E&M Tie Line Wink Start (DTMF and Dial Pulse)
  • E&M Tie Line Immediate Start (DTMF and Dial Pulse)

T1 gives the system the advantages of advanced digital calling as well as conserving PCB slots. For example, you can set up a system with 12 loop start lines, six tie lines, and six DID lines and use only a single PCB slot. Additionally, the T1 PCB has its own on-board processor and DSP so it minimally impacts other system resources.

Note: Although the T1 PCB can connect directly to the telco’s T1 smart jack, your telco may require that you purchase and install a separate Channel Service Unit (CSU). This unit installs between the smart jack and the T1 PCB.

ANI/DNIS Support

The system is compatible with telco's T1 Automatic Number Identification (ANI) and Dialed Number Information Service (DNIS) services. ANI/DNIS services can be provided on T1 loop start, ground start, and DID lines (but not E&M). ANI/DNIS Compatibility provides:
  • Selectable Receive Format
    • You can set up the system for compatibility with any combination of ANI, DNIS and Dialed Number (Address) data provided by the telco.
  • Flexible Routing for DID Lines
    • For DID lines, the system can route the incoming call based on the received DNIS data and the entries stored in the DID Translation Table. See Direct Inward Dialing for more.
  • Caller ID
    • The system can use the received ANI data to display the caller’s number on the called extension’s display. The ANI data can be up to 10 digits long.

FSK Caller ID

The T1 PCB can also receive FSK-based Caller ID (if provided by the telco), the same as the COIU (analog) line cards. To receive this type of Caller ID, you must enable DSP Caller ID for the T1 line circuits in programming.

Conditions and Defaults


  • None.

Default Setting

  • Disabled.

Other Related Features


  • Direct Inward Dialing
    • Directly dial system extensions from outside the system.
  • Tie Lines
    • Link two systems together for inter-system Intercom calling and other features.

IntraMail Features

  • None.