Testing

T1 Loopback

T1 Network

ReceiveTransmit

ICX-250

LIU

FRAMER

CPU

ReceiveTransmit

CPE Device

Network or Remote Loopback

The incoming T1 signal is looped inside the T1 Framer and returned to the T1 Network. This exercises the T1 Line Interface Unit and the T1 Framer with the exception of the HDLC controller and clock switching circuitry.

Issue 1, September 1998

© 1998, ADC Telecommunications, Inc.

ICX-250 Diagnostics

55

T1 Network

ReceiveTransmit

ICX-250

LIU

FRAMER

CPU

ReceiveTransmit

CPE Device

Local Loopback

The outgoing T1 signal is looped inside the T1 LIU and returned to the CPE Device. This exercises the T1 Line Interface Unit, the T1 Framer, CPU, Data Port Interface, and the FXS Interface with the exception of the HDLC controller. The data ports can be exercised up to full T1 rate.

11277-A

ADCP-62-023