1 /*

     2 * Copyright (c) 1999 - 2001 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 *

    16 */

    17 

    18 

    19  /* 

    20    $Workfile: scr_opcodes.c $

    21 

    22     Purpose:

    23 

    24       Inline parameters have been used to optimally pack information into as

    25       few bytes as possible.  Therefore the opcodes types are:

    26       1XXPPPPP  ==> type0

    27       010XPPPP  ==> type1

    28       011XXPPP  ==> type2

    29       00XXXXXX  ==> type3

    30       This file parses the opcode and return its type and any parameters/instrunctions

    31       that has been packed with it.

    32  */

    33         

    34 #include "scr_defs.h"

    35 

    36 void parse_opcode(NW_Byte *opcode, NW_Byte *param)

    37 {

    38   /* 1XXPPPP */

    39   if ((*opcode & 0x80) == 0x80) {

    40     *param  = (NW_Byte)(*opcode & 0x1F);

    41     *opcode = (NW_Byte)(*opcode & 0xE0);

    42   }

    43 

    44   /* 010XPPPP */

    45   else if ((*opcode & 0xE0) == 0x40) {

    46     *param  = (NW_Byte)(*opcode & 0x0F);

    47     *opcode = (NW_Byte)(*opcode & 0xF0);

    48   }

    49 

    50   /* 011XXPPP */

    51   else if ((*opcode & 0xE0) == 0x60 ) {

    52     *param  = (NW_Byte)(*opcode & 0x07);

    53     *opcode = (NW_Byte)(*opcode & 0x78);

    54   }

    55 }