[TimeQuest] Some asynchronous signals detected as clocks

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if (rising_edge(clock)) then
    signal_load_old <= signal_load;
    if ((signal_load_old = '0') and (signal_load = '1')) then
        {do something}
    end if;
end if;

This is only one method to catch the edges of a signal. There are sure some others (perhaps better).

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Thank for your support.

I think I've got to the point. However I have not understood this method of catching edges. How can be signal_load_old and signal_load be different if before the 'if' statement there is a signal assignment between them?

Could another method of catching asynchronous edges be the following?

if (signal_load'event and signal_load = '1') then
   <do something>
end if;