please help me check my coding

R

raullim7

ontime range is 0,1,2.. to 199.
count1a range is 1, 3, 5 .. to 199 (odd numbers).
count1b range is 0, 2, 4 .. to 198 (even numbers).
counter1 range is 0,1,2... to 99.

i have two processes both with same input signal clk. 1st process will
count the rising edge while the 2nd process will count the falling
edge. time between rising edge and falling edge is 5ns.
when i run this code in simulation, i am able to achieve 5ns increment
from the output when i increment the ontime by 1.
but when i do the experiment on the circuit, i can only achieve 10ns
increment. for example, the results i got for ontime= 100, 101, 102,
103, 104, 105 are 40ns, 50ns, 50ns, 60ns, 60ns, 70ns respectively.

may i know where did i went wrong in my coding or is there any illegal
statement? please advise.. thank you.


process (clk, reset) --first process to take care of rising edge
if reset = '0' then
count1a := 1;
elsif (rising_edge(clk)) then
if (counter1 = 0) then
count1a := 1; --count1a will be odd number, 1, 3, 5 .. 199.
else
count1a := count1a + 1;
end if;
end if;
end process;

process (clk, reset) --2nd process to take care of falling edge
if reset = '0' then
count1b := 0; --count1b will be even numbers, 0, 2, 4 .. 198.
counter1 := 0;
elsif (falling_edge(clk)) then
if (counter1 = 0) then
count1b := 0;
end if;
if (counter1 >= 99) then
counter1 := 0;
else
counter1 := counter1 + 1;
count1b := count1b + 2;
end if;
ontime := XX;
ontime1 := XX + 1;
if (ontime1/2 = ontime/2) then --even ontime number
if(count1b < ontime) then
out1 <= '1'; -- out1 is my output signal
else
out1 <= '0';
end if;
else -- odd ontime number
if(count1a < ontime) then
out1 <= '1';
else
out1 <= '0';
end if;
end if;
end process;
 
R

raullim7

process (clk, reset) --first process to take care of rising edge
if reset = '0' then
count1a := 1;
elsif (rising_edge(clk)) then
if (counter1 = 0) then
count1a := 1; --count1a will be odd number, 1, 3, 5 .. 199.
else
count1a := count1a + 2;
end if;
end if;
end process;

**made a mistake here, should be count1a := count1a + 2, not + 1.
 

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