原创 assert & deassert

assert一般理解成有效，好比说这个信号是低电平有效，就是说这个信号在asserted状态时是低电平。deassert反之。

例如：这是MegaWizard中FIFO说明中两句：Deassert the wrreq signal in the same clock cycle when the wrfull signal is deasserted.

Assert this signal to request for a write operation.