计时器VHDL代码
时间: 2023-07-09 14:22:15 浏览: 54
下面是一个简单的计时器的VHDL代码:
```
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity timer is
port(
clk : in std_logic;
rst : in std_logic;
en : in std_logic;
count : in unsigned(15 downto 0);
timeout : out std_logic
);
end entity timer;
architecture rtl of timer is
signal counter : unsigned(15 downto 0) := (others => '0');
begin
process(clk, rst)
begin
if rst = '1' then
counter <= (others => '0');
timeout <= '0';
elsif rising_edge(clk) then
if en = '1' then
counter <= counter + 1;
if counter = count then
timeout <= '1';
else
timeout <= '0';
end if;
end if;
end if;
end process;
end architecture rtl;
```
这个计时器可以接受时钟信号、复位信号、启用信号和计数值。当启用信号为高电平时,计时器开始计数。当计数值达到指定值时,计时器输出一个高电平信号表示计时器已超时。