gba/IodineGBA/core/cartridge/FLASH.js

"use strict";
/*
 Copyright (C) 2012-2013 Grant Galitz
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
function GameBoyAdvanceFLASHChip(is128, isAteml) {
    this.largestSizePossible = (!!is128) ? 0x20000 : 0x10000;
    this.notATMEL = !isAteml;
    this.saves = null;
    this.BANKOffset = 0;
    this.flashCommandUnlockStage = 0;
    this.flashCommand = 0;
    this.writeBytesLeft = 0;
}
GameBoyAdvanceFLASHChip.prototype.initialize = function () {
    this.allocate();
}
GameBoyAdvanceFLASHChip.prototype.allocate = function () {
    if (this.saves == null || (this.saves.length | 0) < (this.largestSizePossible | 0)) {
        //Allocate the new array:
        var newSave = getUint8Array(this.largestSizePossible | 0);
        //Init to default value:
        for (var index = 0; (index | 0) < (this.largestSizePossible | 0); index = ((index | 0) + 1) | 0) {
            newSave[index | 0] = 0xFF;
        }
        //Copy the old save data out:
        if (this.saves != null) {
            for (var index = 0; (index | 0) < (this.saves.length | 0); index = ((index | 0) + 1) | 0) {
                newSave[index | 0] = this.saves[index | 0] | 0;
            }
        }
        //Assign the new array out:
        this.saves = newSave;
    }
}
GameBoyAdvanceFLASHChip.prototype.load = function (save) {
    if ((save.length | 0) == 0x10000 || (save.length | 0) == 0x20000) {
        this.saves = save;
        if ((save.length | 0) == 0x20000) {
            this.notATMEL = true;
        }
    }
}
GameBoyAdvanceFLASHChip.prototype.read = function (address) {
    address = address | 0;
    var data = 0;
    if ((this.flashCommand | 0) != 2 || (address | 0) > 1) {
        data = this.saves[address | this.BANKOffset] | 0;
    }
    else {
        if ((address | 0) == 0) {
            if (this.notATMEL) {
                data = ((this.largestSizePossible | 0) == 0x20000) ? 0x62 : 0xBF;
            }
            else {
                data = 0x1F;
            }
        }
        else {
            if (this.notATMEL) {
                data = ((this.largestSizePossible | 0) == 0x20000) ? 0x13 : 0xD4;
            }
            else {
                data = 0x3D;
            }
        }
    }
    return data | 0;
}
GameBoyAdvanceFLASHChip.prototype.write = function (address, data) {
    address = address | 0;
    data = data | 0;
    switch (this.writeBytesLeft | 0) {
        case 0:
            this.writeControlBits(address | 0, data | 0);
            break;
        case 0x80:
            var addressToErase = (address & 0xFF80) | this.BANKOffset;
            for (var index = 0; (index | 0) < 0x80; index = ((index | 0) + 1) | 0) {
                this.saves[addressToErase | index] = 0xFF;
            }
        default:
            this.writeByte(address | 0, data | 0);
            
    }
}
GameBoyAdvanceFLASHChip.prototype.writeControlBits = function (address, data) {
    address = address | 0;
    data = data | 0;
    switch (address | 0) {
        case 0:
            this.sectorEraseOrBankSwitch(address | 0, data | 0);
            break;
        case 0x5555:
            this.controlWriteStage2(data | 0);
            break;
        case 0x2AAA:
            this.controlWriteStageIncrement(data | 0);
            break;
        default:
            this.sectorErase(address | 0, data | 0);
    }
}
GameBoyAdvanceFLASHChip.prototype.writeByte = function (address, data) {
    address = address | 0;
    data = data | 0;
    this.saves[address | this.BANKOffset] = data | 0;
    this.writeBytesLeft = ((this.writeBytesLeft | 0) - 1) | 0;
}
GameBoyAdvanceFLASHChip.prototype.selectBank = function (bankNumber) {
    bankNumber = bankNumber | 0;
    this.BANKOffset = (bankNumber & 0x1) << 16;
    this.largestSizePossible = Math.max((0x10000 + (this.BANKOffset | 0)) | 0, this.largestSizePossible | 0) | 0;
    this.notATMEL = true;
    this.allocate();
}
GameBoyAdvanceFLASHChip.prototype.controlWriteStage2 = function (data) {
    data = data | 0;
    if ((data | 0) == 0xAA) {
        //Initial Command:
        this.flashCommandUnlockStage = 1;
    }
    else if ((this.flashCommandUnlockStage | 0) == 2) {
        switch (data | 0) {
            case 0x10:
                //Command Erase Chip:
                if ((this.flashCommand | 0) == 1) {
                    for (var index = 0; (index | 0) < (this.largestSizePossible | 0); index = ((index | 0) + 1) | 0) {
                        this.saves[index | 0] = 0xFF;
                    }
                }
                this.flashCommand = 0;
                break;
            case 0x80:
                //Command Erase:
                this.flashCommand = 1;
                break;
            case 0x90:
                //Command ID:
                this.flashCommand = 2;
                break;
            case 0xA0:
                //Command Write:
                this.writeCommandTrigger();
                break;
            case 0xB0:
                //Command Bank Switch:
                this.flashCommand = 3;
                break;
            default:
                this.flashCommand = 0;
        }
        //Reset the command state:
        this.flashCommandUnlockStage = 0;
    }
    else if ((data | 0) == 0xF0) {
        //Command Clear:
        this.flashCommand = 0;
        this.flashCommandUnlockStage = 0;
        this.notATMEL = true;
    }
}
GameBoyAdvanceFLASHChip.prototype.writeCommandTrigger = function () {
    if ((this.flashCommandUnlockStage | 0) == 2) {
        if (this.notATMEL) {
            this.writeBytesLeft = 1;
        }
        else {
            this.writeBytesLeft = 0x80;
        }
    }
}
GameBoyAdvanceFLASHChip.prototype.sectorErase = function (address, data) {
    address = (address << 12) >> 12;
    data = data | 0;
    if ((this.flashCommand | 0) == 1 && (this.flashCommandUnlockStage | 0) == 2 && ((data | 0) == 0x30)) {
        var addressEnd = ((address | this.BANKOffset) + 0x1000) | 0;
        for (var index = address | this.BANKOffset; (index | 0) < (addressEnd | 0); index = ((index | 0) + 1) | 0) {
            this.saves[index | 0] = 0xFF;
        }
        this.notATMEL = true;
    }
    this.flashCommand = 0;
    this.flashCommandUnlockStage = 0;
}
GameBoyAdvanceFLASHChip.prototype.sectorEraseOrBankSwitch = function (address, data) {
    address = address | 0;
    data = data | 0;
    if ((this.flashCommandUnlockStage | 0) == 2) {
        this.sectorErase(address | 0, data | 0);
    }
    else if ((this.flashCommand | 0) == 3 && (this.flashCommandUnlockStage | 0) == 0) {
        this.selectBank(data & 0x1);
    }
    this.flashCommand = 0;
    this.flashCommandUnlockStage = 0;
}
GameBoyAdvanceFLASHChip.prototype.controlWriteStageIncrement = function (data) {
    if ((data | 0) == 0x55 && (this.flashCommandUnlockStage | 0) == 1) {
        this.flashCommandUnlockStage = ((this.flashCommandUnlockStage | 0) + 1) | 0;
    }
    else {
        this.flashCommandUnlockStage = 0;
    }
}