AR# 55841


QSGMII v2.0 - Update to RX termination for 7 Series GTH Transceivers


If using the QSGMII core v3.0 and earlier to target Virtex-7 devices with GTH transceivers, the RX termination is set to AVTT while the latest recommendation in the GTH transceiver User Guides is to set the RX termination to programmable 800 mV. If using the GTX transceiver, the termination is already set to programmable 800 mV.  If using GTP transceiver, the termination is already set to AVTT.


To change the RX termination to 800 mV for Virtex-7 GTH transceiver:

  • in the core_name_gth_gtwizard_gt.v/vhd file, change to use the following settings:
    RX_CM_SEL [1:0] = 2'b11
    RXDFEAGCTRL.[4:3] to  2'b10
    RX_CM_TRIM = 4'b1010

Linked Answer Records

Associated Answer Records

AR# 55841
Date 05/09/2013
Status Active
Type General Article
People Also Viewed