Subversion Repositories mod_mult_exp

library ieee;

use ieee.std_logic_1164.all;

use std.textio.all;

package txt_util is

    -- prints a message to the screen

    procedure print(text: string);

    -- prints the message when active

    -- useful for debug switches

    procedure print(active: boolean; text: string);

    -- converts std_logic into a character

    function chr(sl: std_logic) return character;

    -- converts std_logic into a string (1 to 1)

    function str(sl: std_logic) return string;

    -- converts std_logic_vector into a string (binary base)

    function str(slv: std_logic_vector) return string;

    -- converts boolean into a string

    function str(b: boolean) return string;

    -- converts an integer into a single character

    -- (can also be used for hex conversion and other bases)

    function chr(int: integer) return character;

    -- converts integer into string using specified base

    function str(int: integer; base: integer) return string;

    -- converts integer to string, using base 10

    function str(int: integer) return string;

    -- convert std_logic_vector into a string in hex format

    function hstr(slv: std_logic_vector) return string;

    -- functions to manipulate strings

    -----------------------------------

    -- convert a character to upper case

    function to_upper(c: character) return character;

    -- convert a character to lower case

    function to_lower(c: character) return character;

    -- convert a string to upper case

    function to_upper(s: string) return string;

    -- convert a string to lower case

    function to_lower(s: string) return string;

    -- functions to convert strings into other formats

    --------------------------------------------------

    -- converts a character into std_logic

    function to_std_logic(c: character) return std_logic;

    -- converts a string into std_logic_vector

    function to_std_logic_vector(s: string) return std_logic_vector;

    -- file I/O

    -----------

    -- read variable length string from input file

    procedure str_read(file in_file: TEXT;

                       res_string: out string);

    -- print string to a file and start new line

    procedure print(file out_file: TEXT;

                    new_string: in  string);

    -- print character to a file and start new line

    procedure print(file out_file: TEXT;

                    char:       in  character);

end txt_util;

package body txt_util is

   -- prints text to the screen

   procedure print(text: string) is

     variable msg_line: line;

     begin

       write(msg_line, text);

       writeline(output, msg_line);

   end print;

   -- prints text to the screen when active

   procedure print(active: boolean; text: string)  is

     begin

      if active then

         print(text);

      end if;

   end print;

   -- converts std_logic into a character

   function chr(sl: std_logic) return character is

    variable c: character;

    begin

      case sl is

         when 'U' => c:= 'U';

         when 'X' => c:= 'X';

         when '0' => c:= '0';

         when '1' => c:= '1';

         when 'Z' => c:= 'Z';

         when 'W' => c:= 'W';

         when 'L' => c:= 'L';

         when 'H' => c:= 'H';

         when '-' => c:= '-';

      end case;

    return c;

   end chr;

   -- converts std_logic into a string (1 to 1)

   function str(sl: std_logic) return string is

    variable s: string(1 to 1);

    begin

        s(1) := chr(sl);

        return s;

   end str;

   -- converts std_logic_vector into a string (binary base)

   -- (this also takes care of the fact that the range of

   --  a string is natural while a std_logic_vector may

   --  have an integer range)

   function str(slv: std_logic_vector) return string is

     variable result : string (1 to slv'length);

     variable r : integer;

   begin

     r := 1;

     for i in slv'range loop

        result(r) := chr(slv(i));

        r := r + 1;

     end loop;

     return result;

   end str;

   function str(b: boolean) return string is

    begin

       if b then

          return "true";

      else

        return "false";

       end if;

    end str;

   -- converts an integer into a character

   -- for 0 to 9 the obvious mapping is used, higher

   -- values are mapped to the characters A-Z

   -- (this is usefull for systems with base > 10)

   -- (adapted from Steve Vogwell's posting in comp.lang.vhdl)

   function chr(int: integer) return character is

    variable c: character;

   begin

        case int is

          when  0 => c := '0';

          when  1 => c := '1';

          when  2 => c := '2';

          when  3 => c := '3';

          when  4 => c := '4';

          when  5 => c := '5';

          when  6 => c := '6';

          when  7 => c := '7';

          when  8 => c := '8';

          when  9 => c := '9';

          when 10 => c := 'A';

          when 11 => c := 'B';

          when 12 => c := 'C';

          when 13 => c := 'D';

          when 14 => c := 'E';

          when 15 => c := 'F';

          when 16 => c := 'G';

          when 17 => c := 'H';

          when 18 => c := 'I';

          when 19 => c := 'J';

          when 20 => c := 'K';

          when 21 => c := 'L';

          when 22 => c := 'M';

          when 23 => c := 'N';

          when 24 => c := 'O';

          when 25 => c := 'P';

          when 26 => c := 'Q';

          when 27 => c := 'R';

          when 28 => c := 'S';

          when 29 => c := 'T';

          when 30 => c := 'U';

          when 31 => c := 'V';

          when 32 => c := 'W';

          when 33 => c := 'X';

          when 34 => c := 'Y';

          when 35 => c := 'Z';

          when others => c := '?';

        end case;

        return c;

    end chr;

   -- convert integer to string using specified base

   -- (adapted from Steve Vogwell's posting in comp.lang.vhdl)

   function str(int: integer; base: integer) return string is

    variable temp:      string(1 to 10);

    variable num:       integer;

    variable abs_int:   integer;

    variable len:       integer := 1;

    variable power:     integer := 1;

   begin

    -- bug fix for negative numbers

    abs_int := abs(int);

    num     := abs_int;

    while num >= base loop                     -- Determine how many

      len := len + 1;                          -- characters required

      num := num / base;                       -- to represent the

    end loop ;                                 -- number.

    for i in len downto 1 loop                 -- Convert the number to

      temp(i) := chr(abs_int/power mod base);  -- a string starting

      power := power * base;                   -- with the right hand

    end loop ;                                 -- side.

    -- return result and add sign if required

    if int < 0 then

       return '-'& temp(1 to len);

     else

       return temp(1 to len);

    end if;

   end str;

  -- convert integer to string, using base 10

  function str(int: integer) return string is

   begin

    return str(int, 10) ;

   end str;

   -- converts a std_logic_vector into a hex string.

   function hstr(slv: std_logic_vector) return string is

       variable hexlen: integer;

       variable longslv : std_logic_vector(67 downto 0) := (others => '0');

       variable hex : string(1 to 16);

       variable fourbit : std_logic_vector(3 downto 0);

     begin

       hexlen := (slv'left+1)/4;

       if (slv'left+1) mod 4 /= 0 then

         hexlen := hexlen + 1;

       end if;

       longslv(slv'left downto 0) := slv;

       for i in (hexlen -1) downto 0 loop

         fourbit := longslv(((i*4)+3) downto (i*4));

         case fourbit is

           when "0000" => hex(hexlen -I) := '0';

           when "0001" => hex(hexlen -I) := '1';

           when "0010" => hex(hexlen -I) := '2';

           when "0011" => hex(hexlen -I) := '3';

           when "0100" => hex(hexlen -I) := '4';

           when "0101" => hex(hexlen -I) := '5';

           when "0110" => hex(hexlen -I) := '6';

           when "0111" => hex(hexlen -I) := '7';

           when "1000" => hex(hexlen -I) := '8';

           when "1001" => hex(hexlen -I) := '9';

           when "1010" => hex(hexlen -I) := 'A';

           when "1011" => hex(hexlen -I) := 'B';

           when "1100" => hex(hexlen -I) := 'C';

           when "1101" => hex(hexlen -I) := 'D';

           when "1110" => hex(hexlen -I) := 'E';

           when "1111" => hex(hexlen -I) := 'F';

           when "ZZZZ" => hex(hexlen -I) := 'z';

           when "UUUU" => hex(hexlen -I) := 'u';

           when "XXXX" => hex(hexlen -I) := 'x';

           when others => hex(hexlen -I) := '?';

         end case;

       end loop;

       return hex(1 to hexlen);

     end hstr;

   -- functions to manipulate strings

   -----------------------------------

   -- convert a character to upper case

   function to_upper(c: character) return character is

      variable u: character;

    begin

       case c is

        when 'a' => u := 'A';

        when 'b' => u := 'B';

        when 'c' => u := 'C';

        when 'd' => u := 'D';

        when 'e' => u := 'E';

        when 'f' => u := 'F';

        when 'g' => u := 'G';

        when 'h' => u := 'H';

        when 'i' => u := 'I';

        when 'j' => u := 'J';

        when 'k' => u := 'K';

        when 'l' => u := 'L';

        when 'm' => u := 'M';

        when 'n' => u := 'N';

        when 'o' => u := 'O';

        when 'p' => u := 'P';

        when 'q' => u := 'Q';

        when 'r' => u := 'R';

        when 's' => u := 'S';

        when 't' => u := 'T';

        when 'u' => u := 'U';

        when 'v' => u := 'V';

        when 'w' => u := 'W';

        when 'x' => u := 'X';

        when 'y' => u := 'Y';

        when 'z' => u := 'Z';

        when others => u := c;

    end case;

      return u;

   end to_upper;

   -- convert a character to lower case

   function to_lower(c: character) return character is

      variable l: character;

    begin

       case c is

        when 'A' => l := 'a';

        when 'B' => l := 'b';

        when 'C' => l := 'c';

        when 'D' => l := 'd';

        when 'E' => l := 'e';

        when 'F' => l := 'f';

        when 'G' => l := 'g';

        when 'H' => l := 'h';

        when 'I' => l := 'i';

        when 'J' => l := 'j';

        when 'K' => l := 'k';

        when 'L' => l := 'l';

        when 'M' => l := 'm';

        when 'N' => l := 'n';

        when 'O' => l := 'o';

        when 'P' => l := 'p';

        when 'Q' => l := 'q';

        when 'R' => l := 'r';

        when 'S' => l := 's';

        when 'T' => l := 't';

        when 'U' => l := 'u';

        when 'V' => l := 'v';

        when 'W' => l := 'w';

        when 'X' => l := 'x';

        when 'Y' => l := 'y';

        when 'Z' => l := 'z';

        when others => l := c;

    end case;

      return l;

   end to_lower;

   -- convert a string to upper case

   function to_upper(s: string) return string is

     variable uppercase: string (s'range);

   begin

     for i in s'range loop

        uppercase(i):= to_upper(s(i));

     end loop;

     return uppercase;

   end to_upper;

   -- convert a string to lower case

   function to_lower(s: string) return string is

     variable lowercase: string (s'range);

   begin

     for i in s'range loop

        lowercase(i):= to_lower(s(i));

     end loop;

     return lowercase;

   end to_lower;

-- functions to convert strings into other types

-- converts a character into a std_logic

function to_std_logic(c: character) return std_logic is

    variable sl: std_logic;

    begin

      case c is

        when 'U' =>

           sl := 'U';

        when 'X' =>

           sl := 'X';

        when '0' =>

           sl := '0';

        when '1' =>

           sl := '1';

        when 'Z' =>

           sl := 'Z';

        when 'W' =>

           sl := 'W';

        when 'L' =>

           sl := 'L';

        when 'H' =>

           sl := 'H';

        when '-' =>

           sl := '-';

        when others =>

           sl := 'X';

    end case;

   return sl;

  end to_std_logic;

-- converts a string into std_logic_vector

function to_std_logic_vector(s: string) return std_logic_vector is

  variable slv: std_logic_vector(s'high-s'low downto 0);

  variable k: integer;

begin

   k := s'high-s'low;

  for i in s'range loop

     slv(k) := to_std_logic(s(i));

     k      := k - 1;

  end loop;

  return slv;

end to_std_logic_vector;

----------------

--  file I/O  --

----------------

-- read variable length string from input file

procedure str_read(file in_file: TEXT;

                   res_string: out string) is

       variable l:         line;

       variable c:         character;

       variable is_string: boolean;

   begin

     readline(in_file, l);

     -- clear the contents of the result string

     for i in res_string'range loop

         res_string(i) := ' ';

     end loop;

     -- read all characters of the line, up to the length  

     -- of the results string

     for i in res_string'range loop

        read(l, c, is_string);

        res_string(i) := c;

        if not is_string then -- found end of line

           exit;

        end if;

     end loop;

end str_read;

-- print string to a file

procedure print(file out_file: TEXT;

                new_string: in  string) is

       variable l: line;

   begin

     write(l, new_string);

     writeline(out_file, l);

end print;

-- print character to a file and start new line

procedure print(file out_file: TEXT;

                char: in  character) is

       variable l: line;

   begin

     write(l, char);

     writeline(out_file, l);

end print;

-- appends contents of a string to a file until line feed occurs

-- (LF is considered to be the end of the string)

procedure str_write(file out_file: TEXT;

                    new_string: in  string) is

 begin

   for i in new_string'range loop

      print(out_file, new_string(i));

      if new_string(i) = LF then -- end of string

         exit;

      end if;

   end loop;

end str_write;

end txt_util;