DEAD TIME TO CONTROL 2 SYNCHRONOUS MOSFET (BUCK CONVERTER) help!!!!!!!

HELLO.

I AM A STUDENT AND I AM TRYING TO IMPLEMENT AN STATE MACHINE TO CONTROL A BUCK CONVERTER. IN THIS PART OF CODE, I AM TRYING TO COMMUTE 2 MOSFET (HIGH SIDE AND LOW SIDE). EACH 20ms MOSFET1 (m1) IS IN "ON" AND MOSFET1 (m2) IN "OFF" AND THEN REVERSE.

UP THIS POINT, THE CODE WORKS. BUT, I NEED TO PROGRAM A DEAD TIME TO PREVENT 2 MOSFETS ARE IN STATE "ON" DURING THE COMMUTATION TO AVOID A DEAD SHORT OF THE SOURCE. I put that this dead time has to be of 60ns. It is to assure that (for example): when m1 pass from state "1" to "0" then count to 60ns and then (we are assured that m1 doesn't work) to active m2 '1'.

the delay part of the code is not here. i don't know how to do. it seems to be easy but....the condition "after" or "wait" is not permited because this code is for implementing and "after" and "wait" is only for simulation!!!

some help? thank you very much in advance!! ​

entity controllersource is

generic(timeM: integer:= 1000000); --20 ms (switching time between Mosfets)

generic(timeR: integer:= 3); --60 ns (delay to avoid being 2 MOSFETS in "on" state at the same time)

Port( clk : in std_logic;

rst : in std_logic;

m1: out std_logic; -- Mosfet HIGH side

m2: out std_logic); -- Mosfet LOW side

end entity;

architecture c1 of controllersource is

signal counter: unsigned(23 downto 0);

signal cont: unsigned(23 downto 0);

signal y: std_logic;

begin

counter: process (clk, rst)

begin

if rst = '1' then

counter<=(others => '0');

cont<=(others => '0');

elsif (clk'EVENT and clk = '1') then -- 1 clock period each 50Mhz

counter<=counter+1;

cont<=cont+1;

if counter=timeM then -- 20ms

counter<=(others => '0');

end if;

if cont=tiempoR then -- 60ns

cont<=(others => '0');

end if;

end if;

end process;

commutation: process (clk, rst)

begin

if rst = '1' then

m1<='1';

m2<='0';

y<='0';

elsif (clk'EVENT and clk = '1') then

if counter=timeM then --every time that arrive to 20ms commute the state of mosfets

if y='0' then

y<='1';

m1<='0';

m2<='1';

else

y<='0';

m2<='0';

m1<='1';

end if;

end if;

end if;

end process;

end c1;