倒计时报警 四短一长报警声
daojishi:PROCESS(CLK,EN)
VARIABLE L:STD_LOGIC_VECTOR(3 DOWNTO 0);
BEGIN
IF CLK'EVENT AND CLK='1' THEN ----10秒倒计时
IF EN='0' THEN
IF L=0 THEN
S<='1'; ---超时连续报警
ELSE
L:=L-1;
S<='0';
END IF;
ELSE
S<='0';
L:="1001";
END IF;
END IF;
CASE L IS
2022-10-17 22:00:53
2KB
EDA
数字钟
1