set_property PACKAGE_PIN U16 [get_ports o]
set_property PACKAGE_PIN E19 [get_ports o2]
set_property PACKAGE_PIN U19 [get_ports o3]
set_property PACKAGE_PIN V19 [get_ports o4]

set_property IOSTANDARD LVCMOS33 [get_ports o]
set_property IOSTANDARD LVCMOS33 [get_ports o2]
set_property IOSTANDARD LVCMOS33 [get_ports o3]
set_property IOSTANDARD LVCMOS33 [get_ports o4]