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Altera_Forum
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13 years ago

Subtracting from a std_logic_vector

library IEEE; use IEEE.std_logic_1164.all; use IEEE.std_logic_arith.all; use IEEE.std_logic_unsigned.all; . . . signal count_val : std_logic_vector(5 downto 0) := "000000"; . . ...
Altera_Forum's avatar
Altera_Forum
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13 years ago

I was trying to create an up/down counter. I am getting confused what will come if I do (-1) on std_logic_vector when it already is equal to "000000". What value should I expect to be detected if do (-1) and than try to do unsigned() of the result in an if statement?