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AR# 61695

QSGMII core -Selection of LPM and DFE modes for Transceiver RX Equalizer


By default, the QSGMII core uses DFE mode.
When DFE Mode is used for low channel loss designs, Disparity and Notintable errors are seen, causing packet loss.
The correct mode needs to be selected to resolve these errors.


The selection of LPM and DFE modes should be determined based on the channel loss in your design.
The section Choosing between LPM and DFE Modes in (UG476) has more detail on which one to select depending on the channel loss.
The below parameters must be changed in the  <core_name>_GTWIZARD_GT.v/vhd file to enable LPM mode.
            .RXCDR_CFG                              (72'h03000023ff10400020),
            .RX_DFE_LPM_CFG                         (16'h0904),
            .RXLPMEN                        (tied_to_vcc_i),
You can also check the parameter changes by using the GT wizard for QSGMII protocol with RX equalization set to LPM.
AR# 61695
Date 03/12/2015
Status Active
Type General Article