用户约束文件中老是报错是什么原因啊，比如

用户约束文件中老是报错是什么原因啊，比如
NET "led<1>"        LOC = "E12"|IOSTANDARD=LVTTL|SLEW=SLOW|DRIVE=4;

ERROR:ConstraintSystem - In file: flow_light.ucf(5): Syntax error.  Ensure that
   the previous constraint specification was terminated with ';'.

这样写会报错 NET "led<1>"        LOC = "E12"|IOSTANDARD=LVTTL|SLEW=SLOW|DRIVE=4; 改成下面的就没错误了，难道是编译器的问题？
NET "led<1>"        LOC = "E12"|IOSTANDARD = LVTTL;
NET "led<1>"        SLEW=SLOW;
NET "led<1>"        DRIVE=4;

全角半角？

肯定加空格的，呵呵，