VHDL中attribute keep of xxx: signal is "true";的用法
attribute keep of error_channelb: signal is "true";用法就是 keep a signal after mapping; 如果要用chipscope和在ucf文件中直接使用信号名的,可用keep这保持,这样可方便我们添加观察信号和添加约束.Often you want to assign a constraint to a parti...
