1、-VHDL語言編寫DS18B20溫度傳感器程序library IEEE; use IEEE.STD_LOGIC_1164.ALL; use IEEE.STD_LOGIC_ARITH.ALL; use IEEE.STD_LOGIC_UNSIGNED.ALL; entity ds18B20 is port(clk : in std_logic; -50MHz dq : inout std_logic; rst: in std_logic; LED : out std_logic; LED2 : out std_logic; LED3 : out std_logic; dataout1,dataou

2、t2,dataout3 : out std_logic_vector(6 downto 0 ); -數(shù)end ds18B20; architecture Behavioral of ds18B20 is TYPE STATE_TYPE is (RESET,CMD_CC,WRITE_BYTE,WRITE_LOW,WRITE_HIGH,READ_BIT, CMD_44,CMD_BE,WAIT800MS,GET_TMP,WAIT4MS); signal STATE: STATE_TYPE:=RESET; signal clk_temp : std_logic:='0' signal

3、clk1m : std_logic; -分頻后得到的1M時鐘 signal cp: std_logic; - 1ms 時鐘signal w : integer range 0 to 2 :=0; - xian shi shun xu signal write_temp : std_logic_vector(7 downto 0):="00000000" signal TMP : std_logic_vector(11 downto 0); signal tmp_bit : std_logic; signal WRITE_BYTE_CNT : integer range 0

4、to 8:=0; signal WRITE_LOW_CNT : integer range 0 to 2:=0; signal WRITE_HIGH_CNT : integer range 0 to 2:=0; signal READ_BIT_CNT : integer range 0 to 3:=0; signal GET_TMP_CNT : integer range 0 to 13:=0; signal cnt : integer range 0 to 100_001:=0; -* signal cnt2 : integer range 0 to 4000001:=0; signal t

5、emp : std_logic; signal data_temp0 : std_logic_vector(15 downto 0); signal decimal0 : std_logic_vector(15 downto 0); signal decimal1 : std_logic_vector(15 downto 0); signal decimal2 : std_logic_vector(15 downto 0); signal decimal3 : std_logic_vector(15 downto 0); signal data_temp1 : std_logic_vector

6、(7 downto 0); signal integer0 : std_logic_vector(7 downto 0); signal integer1 : std_logic_vector(7 downto 0); signal integer2 : std_logic_vector(7 downto 0); signal integer3 : std_logic_vector(7 downto 0); signal integer4 : std_logic_vector(7 downto 0); signal integer5 : std_logic_vector(7 downto 0)

7、; signal integer6 : std_logic_vector(7 downto 0); signal sign : std_logic_vector(7 downto 0); signal count : integer range 0 to 51:=0; signal WRITE_BYTE_FLAG : integer range 0 to 4:=0; function dis(num: std_logic_vector) return std_logic_vector isbegin case num is when "0000" => return

8、"1000000" -0 when "0001" => return "1111001" -1 when "0010" => return "0100100" -2 when "0011" => return "0110000" -3 when "0100" => return "0011001" -4 when "0101" => return "0010

9、010" -5 when "0110" => return "0000010" -6 when "0111" => return "1111000" -7 when "1000" => return "0000000" -8 when "1001" => return "0010000" -9 when "1010" => return "0001000"

10、-A when "1011" => return "0000011" -b when "1100" => return "1000110" -C when "1101" => return "0100001" -d when "1110" => return "0000110" -E when "1111" => return "0001110" -F when ot

11、hers => return "1111111" -mie end case; end dis; begin -ClkDivider:process (clk,clk_temp) begin if rising_edge(clk) then if (count = 24) then count <= 0; clk_temp<= not clk_temp; else count <= count +1; end if; end if; clk1m<=clk_temp; end Process; -process (clk1m) variable

12、n: integer range 0 to 12000:=0;begin -cp 1ms if rising_edge(clk1m) then n:=n+1; if (n>12000) then n:=0; cp<=not cp; end if; end if; end Process; STATE_TRANSITION:process(STATE,clk1m) begin if rising_edge(clk1m) then if(rst='0') then STATE<=RESET; else case STATE is when RESET=> -

13、* LED2<='0'-*- LED3<='0' -* if (cnt>=0 and cnt<500) then - 500s的復(fù)位低電平 dq<='0'- dq作為輸出 cnt<=cnt+1; STATE<=RESET; elsif (cnt>=500 and cnt<510) then -高阻態(tài)再輸入下一級電路的話，對下級電路無任何影響，和沒接一樣,高阻態(tài)可以應(yīng)用在inout端口里面，這樣在inout沒有輸出的時候就弄個高阻態(tài)，這樣就其電平就可以由外面的輸入信號決定了dq<='

14、;Z' cnt<=cnt+1; STATE<=RESET; -拉高dq elsif (cnt>=510 and cnt<750) then - 240stemp<=dq; - dq作為輸入if(cnt=580) then temp<=dq; if(temp='1') then LED<='0' else LED<='1' end if; end if; cnt<=cnt+1; STATE<=RESET; elsif (cnt>=750) then cnt<=0; -計

15、數(shù)器清零 STATE<=CMD_CC; -復(fù)位過程伴隨著跳躍rom指令“CC”end if; when CMD_CC=> -跳躍rom指令“CC”LED2<='1' LED3<='0' write_temp<="11001100" STATE<=WRITE_BYTE; when WRITE_BYTE=> case WRITE_BYTE_CNT is when 0 to 7=> if (write_temp(WRITE_BYTE_CNT)='0') then STATE<=W

16、RITE_LOW; LED3<='1' else STATE<=WRITE_HIGH; end if; WRITE_BYTE_CNT<=WRITE_BYTE_CNT+1; when 8=> if (WRITE_BYTE_FLAG=0) then - 第一次寫0XCC完畢 STATE<=CMD_44; WRITE_BYTE_FLAG<=1; elsif (WRITE_BYTE_FLAG=1) then -寫0X44完畢 (寫溫度轉(zhuǎn)換指令后沒有讀數(shù)據(jù)？) STATE<=RESET; WRITE_BYTE_FLAG<=2; elsif

17、(WRITE_BYTE_FLAG=2) then -第二次寫0XCC完畢 STATE<=CMD_BE; WRITE_BYTE_FLAG<=3; elsif (WRITE_BYTE_FLAG=3) then -寫0XBE完畢 STATE<=GET_TMP; WRITE_BYTE_FLAG<=0; end if; WRITE_BYTE_CNT<=0; when others=>STATE<=RESET; end case; when WRITE_LOW=> LED3<='1' case WRITE_LOW_CNT is when

18、 0=> dq<='0' if (cnt=70) then cnt<=0; WRITE_LOW_CNT<=1; else cnt<=cnt+1; end if; when 1=> dq<='Z' if (cnt=5) then cnt<=0; WRITE_LOW_CNT<=2; else cnt<=cnt+1; end if; when 2=> STATE<=WRITE_BYTE; WRITE_LOW_CNT<=0; when others=>WRITE_LOW_CNT<=

19、0; end case; when WRITE_HIGH=> case WRITE_HIGH_CNT is when 0=> dq<='0' if (cnt=8) then cnt<=0; WRITE_HIGH_CNT<=1; else cnt<=cnt+1; end if; when 1=> dq<='Z' if (cnt=72) then cnt<=0; WRITE_HIGH_CNT<=2; else cnt<=cnt+1; end if; when 2=> STATE<=WRIT

20、E_BYTE; WRITE_HIGH_CNT<=0; when others=>WRITE_HIGH_CNT<=0; end case; when CMD_44=> write_temp<="01000100" STATE<=WRITE_BYTE; when CMD_BE=> write_temp<="10111110" STATE<=WRITE_BYTE;- when READ_BIT=> case READ_BIT_CNT is when 0=> dq<='0'

21、-4s的低電平 if (cnt=4) then READ_BIT_CNT<=1; cnt<=0; else cnt<=cnt+1; end if; when 1=> dq<='Z' -4s的高電平 if (cnt=4) then READ_BIT_CNT<=2; cnt<=0; else cnt<=cnt+1; end if; when 2=> dq<='Z' TMP_BIT<=dq; -12s讀出數(shù)據(jù) ,就是最后一次賦值的結(jié)果。 if (cnt=4) then READ_BIT_CNT<=

22、3; cnt<=0; else cnt<=cnt+1; end if; when 3=> - dq<='Z' -控制器拉高總線- if (cnt=50) then -讀出數(shù)據(jù)后，等待50us cnt<=0; READ_BIT_CNT<=0; STATE<=GET_TMP; else cnt<=cnt+1; end if; when others=>READ_BIT_CNT<=0; end case; -#- when GET_TMP=> case GET_TMP_CNT is when 0 => STATE<=READ_BIT; GET_TMP_CNT<=GET_TMP_CNT+1; when 1 to 12=> STATE<=READ_BIT; TMP(GET_TMP_CNT-1)<=TMP_BIT;-將讀出的每一位數(shù)據(jù)按順序