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-----------------------------------------------------------------------
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-- This file is part of SCARTS.
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--
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-- SCARTS is free software: you can redistribute it and/or modify
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-- it under the terms of the GNU General Public License as published by
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-- the Free Software Foundation, either version 3 of the License, or
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-- (at your option) any later version.
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--
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-- SCARTS is distributed in the hope that it will be useful,
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-- but WITHOUT ANY WARRANTY; without even the implied warranty of
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-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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-- GNU General Public License for more details.
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--
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-- You should have received a copy of the GNU General Public License
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-- along with SCARTS. If not, see <http://www.gnu.org/licenses/>.
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-----------------------------------------------------------------------
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-------------------------------------------------------------------------
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--
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-- Filename: math_pkg.vhd
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-- =========
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--
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-- Short Description:
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-- ==================
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-- Utility Package defining often used mathematical functions
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--
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-------------------------------------------------------------------------
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package math_pkg is
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-- Calculates the logarithm dualis of the operand and rounds up
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-- the result to the next integer value.
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function log2c(constant value : in integer) return integer;
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-- Returns the maximum of the two operands
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function max(constant value1, value2 : in integer) return integer;
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-- Returns the maximum of the three operands
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function max(constant value1, value2, value3 : in integer) return integer;
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end math_pkg;
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package body math_pkg is
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function log2c(constant value : in integer) return integer is
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variable ret_value : integer;
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variable cur_value : integer;
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begin
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ret_value := 0;
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cur_value := 1;
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while cur_value < value loop
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ret_value := ret_value + 1;
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cur_value := cur_value * 2;
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end loop;
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return ret_value;
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end function log2c;
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function max(constant value1, value2 : in integer) return integer is
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variable ret_value : integer;
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begin
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if value1 > value2 then
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ret_value := value1;
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else
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ret_value := value2;
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end if;
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return ret_value;
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end function max;
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function max(constant value1, value2, value3 : in integer) return integer is
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begin
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return max(max(value1, value2), value3);
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end function max;
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end package body math_pkg;
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