Кто сталкивался, подскажите пжл. как правильно назначать пины для диф пар на ml605 board?
В проекте сигнал DDS хочу вывести на FMC разъем. В plan ahead назначаю пины, называю их диф парами, в ucf
Код
NET "dac[0]" IOSTANDARD = LVDS_25;
NET "dac[1]" IOSTANDARD = LVDS_25;
NET "dac[2]" IOSTANDARD = LVDS_25;
NET "dac[3]" IOSTANDARD = LVDS_25;
NET "clk" IOSTANDARD = LVCMOS25;
NET "clk" DRIVE = 12;
NET "clk" SLEW = SLOW;
NET "clk" LOC = J9;
NET "dac[0]" LOC = T33;
NET "dac[1]" LOC = U33;
NET "dac[2]" LOC = V32;
NET "dac[3]" LOC = U31;
NET "dac[1]" IOSTANDARD = LVDS_25;
NET "dac[2]" IOSTANDARD = LVDS_25;
NET "dac[3]" IOSTANDARD = LVDS_25;
NET "clk" IOSTANDARD = LVCMOS25;
NET "clk" DRIVE = 12;
NET "clk" SLEW = SLOW;
NET "clk" LOC = J9;
NET "dac[0]" LOC = T33;
NET "dac[1]" LOC = U33;
NET "dac[2]" LOC = V32;
NET "dac[3]" LOC = U31;
при сборке ошибка
ERROR:Pack:2908 - The I/O component "dac<3>" has an illegal IOSTANDARD value.
The IOB component is configured to use single-ended signaling and can not use
differential IOSTANDARD value LVDS_25. Two ways to rectify this issue are:
1) Change the IOSTANDARD value to a single-ended standard. 2) Correct the I/O
connectivity by instantiating a differential I/O buffer.
Как правильно развести выход DDS dac[3:0] на диф пары?
