定界評論

從 VHDL 2008 開始，註釋也可以在幾行上擴充套件。多行註釋以/*開頭，以*/結束。示例：

/* This process models the state register.
   It has an active low, asynchronous reset
   and is synchronized on the rising edge
   of the clock. */
process(clock, aresetn)
begin
  if aresetn = '0' then
    state <= IDLE;
  elsif rising_edge(clock) then
    state <= next_state;
  end if;
end process;

定界註釋也可以在不到一行的情況下使用：

-- Finally, we decided to skip the reset...
process(clock/*, aresetn*/)
begin
  /*if aresetn = '0' then
    state <= IDLE;
  els*/if rising_edge(clock) then
    state <= next_state;
  end if;
end process;