JustinIO的vb串口类分析和总结.docx

JustinIO 的 vb.NET 版本！（串口操作类） 2007-05-28 09:03 Imports System Imports System.Runtime.InteropServices Namespace JustinIO Class CommPort Public PortNum As String Public BaudRate As Integer Public ByteSize As Byte Public Parity As Byte // 0-4=no,odd,even,mark,space Public StopBits As Byte // 0,1,2 = 1, 1.5, 2 Public ReadTimeout As Integer //comm port win32 file handle Private hComm As Integer = -1 Public Opened As Boolean = False //win32 api constants Private Const GENERIC_READ As Int64 = Private Const GENERIC_WRITE As Int64 = Private Const OPEN_EXISTING As Integer = 3 Private Const INVALID_HANDLE_VALUE As Integer = -1 #Region struct StructLayout(LayoutKind.Sequential) _ Public Structure DCB //taken from c struct in platform sdk Public DCBlength As Integer // sizeof(DCB) Public BaudRate As Integer // 指定当前波特率 current baud rate // these are the c struct bit fields, bit twiddle flag to set Public fBinary As Integer // 指定是否允许二进制模式,在 windows95 中必须主 TRUE binary mode, no EOF check Public fParity As Integer // 指定是否允许奇偶校验 enable parity checking Public fOutxCtsFlow As Integer // 指定 CTS 是否用于检测发送控制，当为TRUE 是 CTS 为 OFF，发送将被挂起。 CTS output flow control Public fOutxDsrFlow As Integer // 指定 CTS 是否用于检测发送控制 DSR output flow control Public fDtrControl As Integer // DTR_CONTROL_DISABLE值将 DTR 置为 OFF, DTR_CONTROL_ENABLE 值将DTR 置为ON, DTR_CONTROL_HANDSHAKE 允许DTR握手 DTR flow control type Public fDsrSensitivity As Integer // 当该值为 TRUE 时 DSR 为 OFF 时接收的字节被忽略 DSR sensitivity Public fTXContinueOnXoff As Integer // 指定当接收缓冲区已满,并且驱动程序已经发送出 XoffChar 字符时发送是否停止。TRUE 时，在接收缓冲区接收到 缓冲区已满的字节 XoffLim 且驱动程序已经发送出 XoffChar 字符中止接收字节之后，发送继续进行。 FALSE 时，在接收缓冲区接收到代表缓冲区已空的字节XonChar 且驱动程序已经发送出恢复发送的 XonChar 之后，发送继续进行。XOFF continues Tx Public fOutX As Integer // TRUE时，接收到 XoffChar 之后便停止发送接收到 XonChar 之后将重新开始 XON/XOFF out flow control Public fInX As Integer // TRUE 时，接收缓冲区接收到代表缓冲区满的 XoffLim 之后，XoffChar 发送出去接收缓冲区接收到代表缓冲区空的 XonLim 之后，XonChar 发送出去XON/XOFF in flow control Public fErrorChar As Integer // 该值为 TRUE 且