I am working with a Saturn Spartan6 dev board with the LX45 version of the FPGA. I've been getting a number of errors stating that the specified GPIO in the UCF file does not actually exist on the part (see error message below). I've made sure to set the correct part (XC6SLX45), package (CSG324), and speed grade (2) in the Design Properties. I've also tried bypassing the error by setting the environment variable, which results in a successful compilation, but the GPIO still doesn't work. Any suggestions? ERROR:MapLib:30 - LOC constraint F7 on ftw_out<21> is invalid: No such site on the device. To bypass this error set the environment variable 'XIL_MAP_LOCWARN'.