Place:866 - Not enough valid sites to place the following IOBs:
IO Standard: Name = LVCMOS25, VREF = NR, VCCO = 2.50, TERM = NONE, DIR =
BIDIR, DRIVE_STR = NR
IO_x_x_x_x_x_x_x
IO_x_x_x_x_x_x
IO_x_x_x_x_x
IO_x_x_x_x
IO_x_x_x
IO_x_x
IO_x
IO
This may be due to either an insufficient number of sites available on the
device, too many prohibited sites,
or incompatible I/O Standards locked or range constrained to I/O Banks with
valid sites.
This situation could possibly be resolved by one (or all) of the
following actions:
a) Grouping IOBs of similar standards into a minimum amount of I/O Banks by
using LOC or range constraints.
b) Maximizing available I/O Banks resources for special IOBs by choosing
lower capacity I/O Banks if possible.
c) If applicable, decreasing the number of user prohibited sites or using a
larger device.
我UCF里根本没有用到LVCMOS25。warnings里也没什么异常啊 |