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Occasional ContributorHow to implement Emulated LVDS OUTPUT buffers? Who can provide me one example?
Frequent ContributorHi Lambert,
Kindly find the transcript from the user guide to perform Emulated LVDS OUTPUT buffers .
Emulated LVDS Buffers in Arria V Devices The Arria V device family supports emulated LVDS: • You can use unutilized true LVDS input channels as emulated LVDS output buffers (eTX) for serializa‐ tion factors of 1 and 2. • The emulated differential output buffers support tri-state capability
Occasional ContributorHi RSree,
I have read that you said "Emulated LVDS Buffers In Arria V Device Handbook " previously. And I tried to use ALTLVDS_TX IP + ALTIOBUF + External resistor network to implement eTX.
Code likes this (one) :
altlvds_tx altlvds_tx_u(.tx_in(a), .tx_inclk(clk), .tx_enalbe(load_en), .tx_out(tx_out));
altiobuf altiobuf_u(.data_in(tx_out), .oe(1'b1), .data_out(tx_out_o));
altiobuf altiobuf_u1(.data_in(tx_out),.oe(1'b1),.data_out(tx_out_n));
assign tx_out_n_o = ~tx_out_n;
SDC like this:
set_instance_assignment -name IO_STANDARD LVDS_E_3R -to tx_out_o
set_instance_assignment -name IO_STANDARN LVDS_E_3R -to tx_out_n_o
set_location_assignment PIN_A23 -to "tx_out_o"
set_location_assignment PIN_A24 -to "tx_out_n_o" (assuming A23 and A24 for DIFFIO_RX)
this method has error when I compile code.
the code (two):
altlvds_tx altlvds_tx_u(.tx_in(a), .tx_inclk(clk), .tx_enalbe(load_en), .tx_out(tx_out));
altiobuf altiobuf_u(.data_in(tx_out), .oe(1'b1), .data_out(tx_out_o), .data_out_b(tx_out_n_o));
SDC like this:
set_instance_assignment -name IO_STANDARD LVDS_E_3R -to tx_out_o
set_location_assignment PIN_A23 -to "tx_out_o"
# set_location_assignment PIN_A24 -to "tx_out_n_o" (assuming A23 and A24 for DIFFIO_RX)
this method has error when I compile code.
the code (three)
altlvds_tx altlvds_tx_u(.tx_in(a), .tx_inclk(clk), .tx_enalbe(load_en), .tx_out(tx_out));
altiobuf altiobuf_u(.data_in(tx_out), .oe(1'b1), .data_out(tx_out_o));
altiobuf altiobuf_u1(.data_in(tx_out),.oe(1'b1),.data_out(tx_out_n));
assign tx_out_n_o = ~tx_out_n;
SDC like this:
# set_instance_assignment -name IO_STANDARD LVDS_E_3R -to tx_out_o
#set_instance_assignment -name IO_STANDARN LVDS_E_3R -to tx_out_n_o
set_location_assignment PIN_A23 -to "tx_out_o"
set_location_assignment PIN_A24 -to "tx_out_n_o" (assuming A23 and A24 for DIFFIO_RX)
this method has error when I compile code.
So I don't know how to implement it , and I can not find one example and have no idea. I need help to resolve this problem. Can you help me?
Thanks,
Lambert
