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Altera_Forum's avatar
Altera_Forum
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12 years ago

Implementing User-Defined "Wait For" time

Disclaimer: I'm a noob I'm trying to implement an entity which takes as an input a 16-bit binary number called bounceWidth( in std_ulogic_vector(15 downto 0)) which will represent the time in ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

If its just a behavioural model, then waits and the like are fine and encouraged to improve sim speed. But in you code you have no wait in your while loop, so it will be an infinite loop in 0 time if interval is greater than 0 when it enters the loop. This is because of the mechanics of vhdl. Signals are only updated when a process suspends eg on a wait.

there are other unusual things in you code, like updating tempq and last interval value outside of the reset or clock branches, so the will be assigned on any change of clock or clear.