xiaoche_text.vhd

关于小车的电机驱动,是利用麦宽调制的方法实现的,是双驱动的电机,制作小车時候抖可以用到.

-- xiaoche_text.vhd
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
use ieee.std_logic_arith.all;
entity xiaoche_text is
port(key_add,key_sub:in std_logic;                 --控制小车加速和减速键
key_qj,key_ht:in std_logic;                        --控制小车前进和后退键
clk:in std_logic;                                  --48MHz时钟信号输入端
reset:in std_logic;                                --复位按键
pwm_out1,pwm_out2,pwm_out3,pwm_out4:out std_logic); --PWM波信号输出端
end;
architecture behave of xiaoche_text is
type state is(st0,st1,st2);
signal s : state;
signal pwm_out_done1,pwm_out_done2 : std_logic;
signal key_add1,key_sub1 : std_logic;
signal dout11,dout21,dout31 : std_logic;
signal dout12,dout22,dout32 : std_logic;
signal count : std_logic_vector(16 downto 0);
signal clk1 : std_logic_vector(9 downto 0);
signal duty_cycle : integer range 0 to 100;        --占空比调节信号
begin
u1:process(clk)                                    --对时钟进行分频得到频率较低的时钟
   begin 
    if clk'event and clk='1' 
       then count<=count+'1';clk1<=clk1+'1';
    end if;
   end process;

   key_add1<=dout11 and dout21 and dout31;         --按键消抖处理
   key_sub1<=dout12 and dout22 and dout32;

u2:process(count(16))                              --利用低频率的时钟进行按键消抖
   begin
    if count(16)'event and count(16)='1'
       then dout11<=key_add;dout21<=dout11;dout31<=dout21;
            dout12<=key_sub;dout22<=dout12;dout32<=dout22;
    end if;
   end process;
u3:process(key_add1,key_sub1,reset,clk)            --按键控制模块
   variable d_c : integer range 0 to 100;
   begin
    if reset='1' then d_c:=50;s<=st0;
    elsif clk'event and clk='1' then
       case s is
        when st0 =>if key_add1='1' then s<=st1;
                   elsif key_sub1='1' then s<=st2;
                   end if;
        when st1 =>if key_add1='0' then d_c:=d_c+10;s<=st0;
                   end if;
        when st2 =>if key_sub1='0' then d_c:=d_c-10;s<=st0;
                   end if;
       end case;
    end if;
   duty_cycle<=d_c;
   end process;
u_pwm:process(clk1(9),reset)                        --PWM波生成模块
      variable freq : integer range 0 to 100;       --PWM波频率调节变量
      begin
       if reset='1' then freq:=0;
       elsif clk1(9)'event and clk1(9)='1'
          then freq:=freq+1;
               if freq<duty_cycle then 
                    pwm_out_done1<='1';pwm_out_done2<='1';
               else pwm_out_done1<='0';pwm_out_done2<='0';
               end if;
       end if;
      end process;
u_control:process(clk,reset)                              --控制小车前进和后退模块
          begin
           if reset='1' then pwm_out1<='1';pwm_out2<='1';pwm_out3<='1';pwm_out4<='1';  --小车复位（停止）
           elsif clk'event and clk='1' then
                if key_qj='1' then pwm_out1<=pwm_out_done1;pwm_out2<='1';
                                   pwm_out3<=pwm_out_done2;pwm_out4<='1';
                elsif key_ht='1' then pwm_out1<='1';pwm_out2<=pwm_out_done1;
                                      pwm_out3<='1';pwm_out4<=pwm_out_done2;
                end if;         
           end if;
          end process; 
end;