FPGA programming ADC0804 for continuous conversion

[Reychard]

Hi everyone,

I'm using an ADC to convert signals from a resistive humidity sensor. I'm trying to get it to work with my Spartan-3 FPGA board such that the conversion process is always outputting values and not just once at a time. I'm outputting the 8-bit value on the 8 LEDs.
Now, what I have so far works only when I flick the switch on and off continuously so that the LEDs show the 8bit value as I vary the humidity.

The code I have for the continuous display of values is very slow and it updates very slow. The following is the code I have;

START_FSM	:	PROCESS (CURR_STATE, INTR)
					BEGIN
					
					READ_DATA <= '0';
					WR <= '0';
					
					CASE CURR_STATE IS
							
							WHEN STARTUP =>
								WR <= '0';
								READ_DATA <= '0';
								NEXT_STATE <= CONVERT;
								
							WHEN CONVERT =>
								IF (INTR = '0' AND STREAM = '1') THEN
									NEXT_STATE <= WAIT500;
								ELSIF (INTR = '0' AND STREAM = '0') THEN
									NEXT_STATE <= READ1;
								ELSE
									NEXT_STATE <= CONVERT;
								END IF;
								WR <= '1';
								READ_DATA <= '0';
															
							WHEN WAIT500 =>
								IF (COUNTER_WAIT = 5000) THEN
									NEXT_STATE <= READ1;
								ELSE
									NEXT_STATE <= WAIT500;
								END IF;
								COUNTER_WAIT <= COUNTER_WAIT + 1;
								
							WHEN READ1 =>
								NEXT_STATE <= CONVERT;
								WR <= '1';
								READ_DATA <= '1';
								
							WHEN OTHERS =>
								NEXT_STATE <= STARTUP;
					END CASE;
					END PROCESS;

The datasheet specifies that Read strobe must occur 8 clock periods (8/fCLK) after assertion of interrupt to guarantee reset of INTR.
The clock I'm using is 50Mhz. Can anyone please help me out here?