os.bas

简单的操作系统程序

Attribute VB_Name = "OS"
Option Explicit
Public Type PCB '进程控制块
    ProcessorID As Byte '记录进程索引值与runcode一样可以用来查找
    ProcessorName As String
    CPUTime As Long
    MemStartAdd As Integer
    MemEndAdd As Integer
    CPUregPC As Integer
    CPUregIR As Integer
    CPUregDR As Byte
    CPUregPSW As Byte
    Presence As Boolean
    
End Type

Public Type Devicelist '设备使用列表
    'ProcessorID As Byte
    Used As Boolean
    DeviceID As Byte
    ReadyListindex As Byte
End Type

Public Type ReaddyList '就绪列表
    'ProcessorID As Byte
    Halt As Boolean 'true时为阻塞
    Presence As Boolean
    PCBindex As Byte
    NeedDevice_indexOfDevicelist As Byte
    NeedDevice_timeOfDevice As Byte
End Type

Public Type Running '运行列表
    'NowProcessorID As Byte '当前运行的进程
    ReadyListindex As Byte
    PCBCount As Byte '记录当前总共进程数PCB 0为没有
    ReadyListCount As Byte '记录当前总共就绪列表数目
End Type

Public Type DiskFile '硬盘文件列表
    Address As Integer
    DataLong As Integer
    Presence As Boolean
    MEMBeginAdd As Integer
    ProcessorName As String
End Type

Public Type DMAValue 'DMA中断列表
    DMATimerCount As Integer
    DMACOUNT As Integer
    MemAdd As Integer
    HDAdd As Integer
End Type

Public Sub Main()
    frmSplash.Show
    Load Dialog
End Sub