Sensirion SHT7x interface in VHDL?

[stelik]

sht71 0000000000000000

Does anyone have code or know anything on interfacing a Sensirion SHT71 (or SHT75) sensor in VHDL? In particular, I am using a Xilinx Coolrunner-II CPLD. I have found various sample codes online (like from the Sensirion's website) as well as assembly codes and such, but nothing in VHDL. I have tried for days, but I haven't even been able to synthesize my code!

If anyone has any info, that would be great. Thanks in advance!

Below is my code:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity getdata is
    Port ( clk : in  STD_LOGIC; --500 KHz clock
           twi : inout  STD_LOGIC;  --P139
           i2c : inout  STD_LOGIC;
			  data : out std_logic_vector(19 downto 0);
           clk_twi : out  STD_LOGIC; --P140
           clk_i2c : out  STD_LOGIC);
end getdata;

architecture Behavioral of getdata is
	signal counter_timing	: std_logic_vector(18 downto 0) := "0000000000000000000";
	signal counter_comms		: std_logic_vector(2 downto 0) := "000";
	signal timingclk  		: std_logic := '1'; --1 Hz clock
	signal clk_comms			: std_logic := '1'; --100 KHz clock
	signal temp 				: std_logic_vector(7 downto 0) := "00000011"; --code for measure temperature
	signal humidity 			: std_logic_vector(7 downto 0) := "00000101"; --code for humidity measurement
	signal data_temp 			: std_logic_vector(15 downto 0) := "0000000000000000";
	signal data_humidity 	: std_logic_vector(15 downto 0) := "0000000000000000";
	signal ack 					: std_logic := '0';
	signal start				: std_logic := '0';
	signal measure				: std_logic := '0';
	signal count				: std_logic_vector(1 downto 0) := "00";
	signal count2				: std_logic_vector(3 downto 0) := "0000";
	signal send					: std_logic := '0';
	signal ackq					: std_logic := '0';
	signal receive				: std_logic := '0';
	signal ackt					: std_logic := '0';
begin
	
	slowclock: process (clk)
		 begin
			--if rising_edge(clk) then
			if clk'Event and clk='1' then
					counter_timing <= counter_timing + 1;
					counter_comms <= counter_comms + 1;
					if counter_timing = "1111010000100011111" then
						timingclk <= not timingclk;
						counter_timing <= "0000000000000000000";
					end if;
					if counter_comms = "100" then
						clk_comms <= not clk_comms; 
						counter_comms <= "000";  
					end if;
			end if;
	end process;
	
	
	
	
	retrieve: process(clk,clk_comms,timingclk)
		begin
			--Unless the sensor is taking a measurement, output the 100 KHz clock to clk_twi and clk_i2c
			if measure = '0' then
				clk_twi <= clk_comms;
				--clk_i2c <= clk_comms;
			else
				ack <= twi;
				if ack = '0' then
					measure <= '0';
					receive <= '1';
				end if;
			end if;
			
			--if rising_edge(timingclk) then
			if timingclk'Event and timingclk = '1' then
				start <= '1';
				twi <= '1';
				--i2c <= '1';
			end if;
			
			--Send the start sequence
			--if start = '1' and falling_edge(clk) then
			if start = '1' and clk'Event and clk='1' then
				count <= count + 1;
				count2 <= count2 + 1;
				if count = "10" then 
					twi <= '0';
					count <= "00";
				end if;
				if count2 = "1100" then
					twi <= '1';
				count <= "00";
				count2 <= "0111"; --Set up counter to send temperature command
				start <= '0';
				send <= '1';
				end if;
			end if;
			
			--if send = '1' and falling_edge(clk_comms) then
			if send = '1' and clk_comms'Event and clk_comms = '1' then
				if count2 = "1111" then
					send <= '0';
					twi <= '1';
					ackq <= '1';
					ack <= twi;
				else
					twi <= temp(conv_integer(count2));
					count2 <= count2 - 1;
				end if;
			end if;
			
			--if ackq = '1' and ack = '0' and rising_edge(clk_comms) then
			if ackq = '1' and ack = '0' and clk_comms'Event and clk_comms = '1' then
				measure <= '1';
				ackq <= '0';
			--elsif ackq = '1' and ack = '1' and rising_edge(clk_comms) then
			elsif ackq = '1' and ack = '1' and clk_comms'Event and clk_comms = '1' then
				measure <= '0';
				ackq <= '0';
			end if;
			
			--if receive = '1' and rising_edge(clk_comms) then
			if receive = '1' and clk_comms'Event and clk_comms = '1' then
				if count2 = "0111" and count = "01" then
					count <= count - 1;
				else
					data_temp(conv_integer(count2)) <= twi;
					count2 <= count2 - 1;
					if count2 = "0111" then
						ackt <= '1';
						receive <= '0';
					elsif count2 = "1111" then
						receive <= '0';
					end if;
				end if;
			end if;
			
			--if ackt = '1' and falling_edge(clk_comms) then
			if ackt = '1' and clk_comms'Event and clk_comms = '1' then
				twi <= '0';
				ackt <= '0';
				receive <= '1';
				count <= "01";
			end if;
				
			data(19 downto 12) <= data_temp(7 downto 0);
			--data(11 downto 0) <= data_humidity(11 downto 0);
	end process;
end Behavioral;