membus.c

/*! \file membus.c \brief Memory Bus Driver for ADuC7026. */
//*****************************************************************************
//
// File Name    : 'membus.c'
// Title        : Memory Bus Driver for ADuC7026
// Author       : Pascal Stang - Copyright (C) 2005
// Created      : 2005.02.14
// Revised      : 2005.02.14
// Version      : 0.1
// Target MCU   : Analog Devices ADuC7026 ARM 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.
//
// This code is distributed under the GNU Public License
//      which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************

#include "aduc7026.h"
#include "global.h"
#include "membus.h"

void membusInit(void)
{
    // enable external memory bus
    XMCFG = 0x01;
    // setup I/O lines
    // setup control lines
    GP2CON |= 0x22222220;
    // setup AD0-15
    GP3CON |= 0x22222222;
    GP4CON |= 0x22222222;

    // setup all memory banks as 16-bit
    XM0CON = XMCON_16BIT | XMCON_ENABLE;
    XM1CON = XMCON_16BIT | XMCON_ENABLE;
    XM2CON = XMCON_16BIT | XMCON_ENABLE;
    XM3CON = XMCON_16BIT | XMCON_ENABLE;

    XM0PAR = XMPAR_16BITADDR | XMPAR_EXTRAHOLD;
    XM1PAR = XMPAR_16BITADDR | XMPAR_EXTRAHOLD;
    XM2PAR = XMPAR_16BITADDR | XMPAR_EXTRAHOLD;
    XM3PAR = XMPAR_16BITADDR | XMPAR_EXTRAHOLD;
}

uint16_t membusRead(uint32_t addr)
{
    return *((unsigned short*)addr);
}

void membusWrite(uint32_t addr, uint16_t data)
{
    *((unsigned short*)addr) = data;
}

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