#set_property LOC R2 [get_ports led]
#OBUF_6
set_property DRIVE 12 [get_ports led[0]]
#OBUF_7
set_property IN_TERM UNTUNED_SPLIT_40 [get_ports led[1]]
set_property SLEW FAST [get_ports led[1]]
set_property IOSTANDARD SSTL135 [get_ports led[1]]
#OBUF_OUT
set_property IN_TERM UNTUNED_SPLIT_50 [get_ports out_a]
set_property SLEW FAST [get_ports out_a]
set_property IOSTANDARD LVCMOS33 [get_ports out_a]
#bottom_inst.OBUF_10
set_property SLEW SLOW [get_ports out_b[0]]
set_property IOSTANDARD LVCMOS18 [get_ports out_b[0]]
#bottom_inst.OBUF_11
set_property DRIVE 4 [get_ports out_b[1]]
set_property SLEW FAST [get_ports out_b[1]]
set_property IOSTANDARD LVCMOS25 [get_ports out_b[1]]
#bottom_inst.OBUF_9
set_property SLEW FAST [get_ports led[2]]
set_property IOSTANDARD DIFF_SSTL135 [get_ports led[2]]
#bottom_intermediate_inst.OBUF_8
set_property DRIVE 16 [get_ports led[3]]
set_property IOSTANDARD SSTL135 [get_ports led[3]]
#set_property INTERNAL_VREF 0.600 [get_iobanks 14]
#set_property INTERNAL_VREF 0.675 [get_iobanks 15]
#set_property INTERNAL_VREF 0.750 [get_iobanks 16]
#set_property INTERNAL_VREF 0.900 [get_iobanks 34]
#set_property INTERNAL_VREF 0.900 [get_iobanks 35]