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Altera_Forum's avatar
Altera_Forum
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17 years ago

errors in quartus when simulation

I have some code about LEDs cycle. I wrote two process, one is a time divider, the other is LED turn on according with divider. the project was complied, but quartus has some errors when staring simu...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Hi I have a similar problem, but i don't put my signal in process sensitive list, so i think it shouldn't make a combinational loop but again i have the same error for oscillating!!!

an interesting point is that the error may disappear in some testcases!!! usually when test case doesn't go in if( inc = '1')!!!

i will be glad if any one can help me!!!

process( reset, shift, add, inc, swap, comp, datain)

begin

if (reset = '1') then

accumulator <= "0000000000000000";

else

if (shift = '1') then

accumulator <= '0' & accumulator(15 downto 1);

else

if (add = '1') then

accumulator <= accumulator + datain;

else

if (inc = '1' ) then

accumulator <= accumulator + 1;

else

if( swap = '1') then

accumulator <= accumulator ( 6 downto 0) & accumulator( 15 downto 7);

else

accumulator <= accumulator;

end if;

end if;

end if;

end if;

end if;

end process;