We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome,
Internet Explorer 11,
Safari. Thank you!
AR# 55841: QSGMII v2.0 - Update to RX termination for 7 Series GTH Transceivers
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