mmu.s

基于EP7312的MP3播放器源代码,包括MCU和PC端代码.

//****************************************************************************
//
// MMU.S - Builds the MMU page table.
//
// Copyright (c) 1999,2000,2001 Cirrus Logic, Inc.
//
//****************************************************************************

#include "../asmdefs.h"

//****************************************************************************
//
// The MMU page table.  The virtual memory map created by this page table
// is as follows:
//
//     0x00000000 - 0x000fffff => 1Meg of program ROM (nCS0)
//     0x00100000 - 0x001fffff => 1Meg of internal SRAM (only 37.5K exists)
//     0x00200000 - 0x002fffff => EP7209 internal registers
//     0x00300000 - 0x003fffff => NAND FLASH interface (nCS1)
//     0x00400000 - 0x004fffff => USB controller (nCS4)
//     0x00500000 - 0x005fffff => LCD controller (nCS2)
//
// The area for the page table is located at the end of the ROM in an effort to
// cut down on the padding added before the page table (since it must be
// aligned on a 16K byte boundary).  This really should have all 4K entries
// populated, but we simply populate the first six entries since that is all
// that we use.  Unpredictable results will occur if the program inadvertently
// accesses a memory location past 6Meg.
//
//****************************************************************************

    _DATA_

    _EXPORT_ PageTable
PageTable _LABEL_
    //
    // Program ROM (nCS0)
    //
    _WORD_  0x00000c12

    //
    // EP7209 internal SRAM
    //
    _WORD_  0x60000c12

    //
    // EP7209 internal registers
    //
    _WORD_  0x80000c12

    //
    // NAND FLASH (nCS1)
    //
    _WORD_  0x10000c12

    //
    // USB controller (nCS4)
    //
    _WORD_  0x40000c12

    //
    // LCD controller (nCS2)
    //
    _WORD_  0x20000c12

    _END_