At Commands For Testing And Debugging - ActionTec IS560LH User Manual

%Cn
Enables or disables data compression negotiation on an error corrected link.
Result Codes:

AT Commands for Testing and Debugging

The following commands are to be used for testing and debugging only and are not
meant for general use.
&&C
&&L
This command provides a loopback for line-to-line.
&&R
Enable/Disable Data Compression
Write to/Read from DSP Register
Line-to-Line Loopback
Write to/Read from DSP RAM Location
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