elsif cnt<5000 then clk_500hz<='0'; else cnt:=0;clk_500hz<='0';
end if;
end if;
end process;
process(clk,dw1) begin
if clk'event and clk='1' then case dw1 is
when 1=>x1<=d;x2<=k;---1 档
when 2=>x1<=k;x2<=d;---10 档
when others=>x1<=\
end case;
end if;
end process;
process(clk,v1,v2,v3,v4,v5) begin
if clk'event and clk='1' then case v1 is when 0=>xv1<=\
when 1=>xv1<=\ when 2=>xv1<=\ when 3=>xv1<=\ when 4=>xv1<=\ when 5=>xv1<=\ when 6=>xv1<=\ when 7=>xv1<=\ when 8=>xv1<=\ when 9=>xv1<=\
when others=>xv1<=\
end case;
case v2 is when 0=>xv2<=\
when 1=>xv2<=\ when 2=>xv2<=\ when 3=>xv2<=\ when 4=>xv2<=\ when 5=>xv2<=\ when 6=>xv2<=\ when 7=>xv2<=\
when 8=>xv2<=\
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when 9=>xv2<=\
when others=>xv2<=\
end case; case v3 is when 0=>xv3<=\
when 1=>xv3<=\ when 2=>xv3<=\ when 3=>xv3<=\ when 4=>xv3<=\ when 5=>xv3<=\ when 6=>xv3<=\ when 7=>xv3<=\ when 8=>xv3<=\ when 9=>xv3<=\
when others=>xv3<=\
end case;
case v4 is when 0=>xv4<=\
when 1=>xv4<=\ when 2=>xv4<=\ when 3=>xv4<=\ when 4=>xv4<=\ when 5=>xv4<=\ when 6=>xv4<=\ when 7=>xv4<=\ when 8=>xv4<=\ when 9=>xv4<=\
when others=>xv4<=\
end case;
case v5 is when 0=>xv5<=\
when 1=>xv5<=\ when 2=>xv5<=\ when 3=>xv5<=\ when 4=>xv5<=\ when 5=>xv5<=\ when 6=>xv5<=\ when 7=>xv5<=\ when 8=>xv5<=\ when 9=>xv5<=\
when others=>xv5<=\
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end case; end if; end process;
process(clk,reset) begin if reset='0'then dataram<=((\ (\
(\
elsif rising_edge(clk)then
dataram(0)<=v; dataram(1)<=g; dataram(2)<=xv1; dataram(3)<=x1; dataram(4)<=xv2; dataram(5)<=x2; dataram(6)<=xv3; dataram(7)<=xv4; dataram(8)<=xv5;
dataram(9)<=dw;
end if;
end process;
process(clk_500hz,reset,dataram) variable cntt,cnt2:integer; begin if reset='0'then current_state<=set_dlnf;
cntt:=0;cnt2:=0;
elsif rising_edge(clk_500hz)then case current_state is when set_dlnf=> lcden<='0'; lcdda<='0'; lcdrw<='0';
lcddata<=\功能设置 cntt:=cntt+1;
if cntt>delay and cntt<=delay*2 then
lcden<='1';
else
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lcden<='0'; end if;
if cntt=delay*3 then
current_state<=clear_lcd; cntt:=0;
end if;
when clear_lcd=> lcden<='0';
lcdda<='0'; lcdrw<='0';
lcddata<=\清屏
cntt:=cntt+1;
lcden<='1';
else
lcden<='0'; end if;
if cntt=delay*3 then
current_state<=set_cursor; cntt:=0;
end if;
lcden<='0'; lcdda<='0'; lcdrw<='0';
lcddata<=\输入方式设置
cntt:=cntt+1;
lcden<='1';
else
lcden<='0'; end if;
if cntt=delay*3 then current_state<=set_dcb; cntt:=0;
end if;
lcden<='0'; lcdda<='0'; lcdrw<='0';
lcddata<=\---显示开关控制
cntt:=cntt+1;
if cntt>delay and cntt<=delay*2 then
lcden<='1';
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if cntt>delay and cntt<=delay*2 then
when set_cursor=>
if cntt>delay and cntt<=delay*2 then
when set_dcb=>
else lcden<='0'; end if;
if cntt=delay*3 then
current_state<=set_location; cntt:=0; end if;
when set_location=>
lcden<='0'; lcdda<='0'; lcdrw<='0';
lcddata<=\ ---DDRAM1设置
cntt:=cntt+1;
if cntt>delay and cntt<=delay*2 then lcden<='1';
else
lcden<='0';
end if;
if cntt=delay*3 then
current_state<=write_data; cntt:=0; end if;
when write_data=>
lcden<='0'; lcdda<='1'; lcdrw<='0'; if cnt2<=9 then
lcddata<=dataram(cnt2); ---写数据
cntt:=cntt+1;
if cntt>delay and cntt<=delay*2 then lcden<='1';
else lcden<='0'; end if;
if cntt=delay*3 then
current_state<=write_data; cntt:=0;
cnt2:=cnt2+1;
end if;
else cnt2:=0;
current_state<=set_cursor;
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