数据输入不能赋值

只看该作者 · 2013-2-21 19:18

PROCESS(pulse_temp,pulse,clk,dat,key)
BEGIN
IF（clk'event and clk='1') THEN
IF(pulse_temp='1' AND pulse='0') THEN
      flag='1';
END IF;
case key IS
when "000" =>  IF(flag='1')  THEN
                           temp2<=dat;
                           flag2='1';
                        END IF;
                        IF(flag2='1') THEN
                              sgnout1<='1';
                              IF(cnt=temp2) THEN
                                 sgnout1<='0';
                              cnt="0000000000" ;
                              flag2<='0';
                                 flag<='0';
                              ELSE
                                 cnt<=cnt+'1';
                           END IF;
                        END IF;