3Com MSR 50, MSR 30 manual T1 sendloopcode, 281

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Example # Create a 128 kbps serial interface through timeslot bundling on the first T1 line on interface T3 2/0.

<Sysname> system-view

[Sysname] interface t3 2/0

[Sysname-T3 2/0] t1 1 channel-set 1 timeslot-list 1,2

t1 sendloopcode

Syntax t1 line-numbersendloopcode { fdl-ansi-line-up fdl-ansi-payload-up fdl-att-payload-up inband-line-up }

undo t1 line-numbersendloopcode { fdl-ansi-line-up fdl-ansi-payload-up fdl-att-payload-up inband-line-up }

View CT3 interface view

Parameter line-number: T1 line number, in the range 1 to 28.

fdl-ansi-line-up: Sends ANSI-compliant LLB activation request code in the FDL to start remote loopback.

fdl-ansi-payload-up: Sends ANSI-compliant PLB activation request code in the FDL to start remote loopback.

fdl-att-payload-up: Sends AT&T-compliant PLB activation request code in the FDL to start remote loopback.

inband-line-up: Sends in-band LLB activation request code compliant with the ANSI and AT&T implementation to start remote loopback.

Description Use the t1 sendloopcode command to set the loopback mode of the specified far-end T1 line.

Use the undo t1 sendloopcode command to remove the corresponding setting.

Loopback is an effective way of diagnosis. You may place a far-end device into loopback mode either at command line on it or by sending loopback control code to it. The types and formats of loopback control code supported on T1 interfaces are compliant with ANSI T1.403.

Loopback can be divided into line loopback and payload loopback. They differ in the sense that the data stream is looped back at the framer with line loopback but not with payload loopback.

You may transmit loopback control code by using the in-band signal (the 192 effective bandwidth bits or all 193 bits of T1) or the FDL in ESF frames.

Example # Send the in-band signal on T1 line 1 on CT3 interface T3 2/0 to place the far-end T1 line in line loopback mode.