fixedpt.h

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/*! \file fixedpt.h \brief Fixed-point math function library. */
//*****************************************************************************
//
// File Name    : 'fixedpt.h'
// Title        : Fixed-point math function library
// Author       : Pascal Stang - Copyright (C) 2003
// Created      : 2003.01.26
// Revised      : 2003.02.04
// Version      : 0.1
// Target MCU   : Atmel AVR Series
// Editor Tabs  : 4
//
// NOTE: This code is currently below version 1.0, and therefore is considered
// to be lacking in some functionality or documentation, or may not be fully
// tested.  Nonetheless, you can expect most functions to work.
//
/// \ingroup general
/// \defgroup fixedpt Fixed-Point Math Function Library (fixedpt.c)
/// \code #include "fixedpt.h" \endcode
/// \par Overview
///     This library provides basic fixed-point math operations implemented in
///     C. Fixed-point math is a system by which integer variables can
///     represent fractional values with a fixed precision "behind" the decimal
///     point (like a fixed number of decimal places).  Fixed-point math is
///     typically 10x faster to execute than floating-point math, and should
///     be used when a limited amount of fractional precision is sufficient
///     (such as 4ths, or 10ths, or 128ths, etc).
///
///     \note This library is really meant more as a demonstration of fixed-pt
///     math.  For best code-efficiency and speed, you are enouraged to take
///     the code you see in these functions and copy it into your own code.
//
// This code is distributed under the GNU Public License
//      which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************

#ifndef FIXEDPT_H
#define FIXEDPT_H

#include "global.h"

// constants/macros/typdefs

// functions

//! fixedptInit() initializes fixed-point math function library
//   set the number of bits to use behind the point
void fixedptInit(u08 fixedPtBits);

//! convert integer to fixed-point number
s32 fixedptConvertFromInt(s32 int_number);

//! convert fixed-point number to integer
s32 fixedptConvertToInt(s32 fp_number);

//! add a and b (a+b) with fixed-point math
s32 fixedptAdd(s32 a, s32 b);

//! subtract a and b (a-b) with fixed-point math
s32 fixedptSubtract(s32 a, s32 b);

//! multiply a and b (a*b) with fixed-point math
s32 fixedptMultiply(s32 a, s32 b);

//! divide numer by denom (numer/denom) with fixed-point math
s32 fixedptDivide(s32 numer, s32 denom);

#endif

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