用TCL分配管脚的方法

#----------------------------------
#TCL PIN assignment
#----------------------------------
#setup pin setting
set_global_assignment -name FAMILY "Cyclone II"
set_global_assignment -name DEVICE EP4CE115F29C7N
# ASSIGNMENT DEVICE
set_global_assignment -name RESERVE_ALL_UNUSED_PINS"as input tri-stated"
set_global_assignment CYCLONEIV_RESERVE_NCEO_AFTER_CONFIGURATION "USE AS REGULAR IO"

set_global_assignment -name ENABLE_INIT_DONE_OUTPUT OFF
#assignment pin
set_global_assignment PIN_(number) -to (custom function)
set_global_assignment PIN_ -to
set_global_assignment PIN_ -to
set_global_assignment PIN_ -to
..............

将未用到的管脚定义为三态普通的IO口