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--===========================================================================--

--

--  S Y N T H E Z I A B L E    miniUART   C O R E

--

--  www.OpenCores.Org - January 2000

--  This core adheres to the GNU public license  

--

-- Design units   : UART_Def

--

-- File name      : uart_lib.vhd

--

-- Purpose        : Implements an miniUART device for communication purposes 

--                  between the OR1K processor and the Host computer through

--                  an RS-232 communication protocol.

--                  

-- Library        : uart_lib.vhd

--

-- Dependencies   : IEEE.Std_Logic_1164

--

--===========================================================================--

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

-- Revision list

-- Version   Author                 Date                        Changes

--

-- 0.1      Ovidiu Lupas     15 January 2000                   New model

--        olupas@opencores.org

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

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

-- package UART_Def

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

library IEEE;

use IEEE.Std_Logic_1164.all;

use IEEE.Numeric_Std.all;

--**--

package UART_Def is

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

      -- Converts unsigned Std_LOGIC_Vector to Integer, leftmost bit is MSB

      -- Error message for unknowns (U, X, W, Z, -), converted to 0

      -- Verifies whether vector is too long (> 16 bits)

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

      function  ToInteger (

         Invector : in  Unsigned(3 downto 0))

       return     Integer;

end UART_Def; --==================== End of package header ======================--

package body UART_Def is

  function  ToInteger (

       InVector : in Unsigned(3 downto 0))

      return  Integer is

    variable Result       : Integer         := 0;

    constant HeaderMsg   : String          := "To_Integer:";

    constant MsgSeverity : Severity_Level  := Warning;

  begin

    for i in 0 to 3 loop

      if (InVector(i) = '1') then

         Result := Result + (2**I);

      end if;

    end loop;

    return Result;

  end ToInteger;

end UART_Def; --================ End of package body ================--