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Altera_Forum's avatar
Altera_Forum
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13 years ago

how to get part of variable of type std_logic_vector like substring function

for example

temp : std_logic_vector[31 downto 0]

just want to get starting from 3th bit to 5th bit and store to another variable of type std_logic_vector[2 downto 0]

like offset

how to write in vhdl?

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    variable temp2 : std_logic_vector(2 downto 0);

    ....

    temp2 := temp(5 downto 3);
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    i mean temp2 : std_logic_vector(6 downto 0) := "011011"

    if want to get from bit 3 to bit 5 which is 101

    does it need to write a substring function or is there a function that can do this?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    I dont quite understand what you mean. You can slice an array like I showed you.

    temp3 := temp2(5 downto 3);