usb_function_module.bas

vb与USB通信的通用编程示例 基于vb的主机编程示例实现对usb的数据传输

Attribute VB_Name = "USB_Proc_Module"
'*******************************************************************************************
'USB操作API
'*******************************************************************************************

Option Explicit

'*******************************************************************************************
'  **  函数名称: USB_Init
'  **  输入参数: 无
'  **  输出参数: 连接设备数量
'  **  函数说明: USB初始化
'*******************************************************************************************
Public Function USB_Init() As Byte
    Dim DevNumTemp As Byte
    
    DevNumTemp = GetTMCDeviceNum
    USB_Init = DevNumTemp
End Function

'*******************************************************************************************
'  **  函数名称: USB_Send
'  **  输入参数:
'  **  DevNo       -- 指定设备号
'  **  InputString -- 传送的命令
'  **  输出参数: 发送是否成功
'  **  函数说明: 向指定设备发送
'*******************************************************************************************
Public Function USB_Send(DevNo As Long, InputString As String) As Boolean
    Dim Commond_Buffer(200) As Byte
    Dim Commond_Length As Long
    Dim i As Long
    
    Commond_Length = Len(InputString)
    
    '转换字符串为字符数组
    For i = 0 To Commond_Length - 1
        Commond_Buffer(i) = Asc(Mid(InputString, i + 1, 1))
    Next i
    

    
    Call BuildBulkbTag
    
    'USB write Proc
    g_bReturn = WriteUSB(DevNo, DEV_DEP_MSG_OUT, bulkOutbTag, Commond_Length, VarPtr(Commond_Buffer(0)))
   
    USB_Send = g_bReturn
    
End Function


'*******************************************************************************************
'  **  函数名称: USB_Read
'  **  输入参数:
'  **  DevNo       -- 指定设备号
'  **  输出参数: 返回的字符串
'  **  函数说明: 从指定设备读取返回值
'*******************************************************************************************
Public Function USB_Read(DevNo As Long) As String
    Dim stringTemp As String
    Dim readsize As Long               '返回值字节数
    Dim reciveBuf(2000000) As Byte        '返回值缓存数组
    Dim i As Long
    Dim ReadSizeTotal As Long
    
    
    ReadSizeTotal = 0
    readsize = 0
    
    'USB Read Proc
        
    Call BuildBulkbTag
    g_bReturn = WriteUSB(DevNo, REQUEST_DEV_DEP_MSG_IN, bulkOutbTag, 0, 0)
    g_bReturn = ReadUSB(DevNo, VarPtr(readsize), VarPtr(reciveBuf(ReadSizeTotal)))
    ReadSizeTotal = ReadSizeTotal + readsize

    
    stringTemp = ""
    
    '数组 --> 字符串
    For i = 0 To ReadSizeTotal
        stringTemp = stringTemp & Chr(reciveBuf(i))
    Next i
    
    USB_Read = stringTemp
End Function