IN SPARTAN 3E BOARD.. THE INTERNAL CLOCK FREQUENCY IS
16MHZ... IF WE WANT TO INTERFACING THE EXT DIPLAY DEVICES
WE WON'T RUN IT WITH A NORMAL CLOCK FREQ(16
MHZ)....THATSWHY I HAVE TO CREATED NEW CLOCK PULSE WITH THE
FREQ OF 1HZ BY DEVIDING THE CLOCK..... TAKE THE NORMAL CLK
AS A REFERENCE...THIS IS KNOWN AS CLOCK DIVIDER CONCEPT...
ENTITY CLK_DIV IS
PORT(CLK: IN STD_LOGIC;
NEWCLK:OUT STD_LOGIC);
END CLK_DIV
ARCH BEH OF CLK_DIV IS
VARIABLE COUNT:INTEGER:=0;
SIGNAL CLKN:STD_LOGIC;
BEGIN
PROCESS(CLK)
BEGIN
IF CLK='1' AND CLK'EVENT THEN
COUNT:=COUNT+1;
IF COUNT=8000000 THEN
NEWCLK<= NOT CLKN
COUNT:=0;
END PROCESS;
END BEH;  |