Последовательный порт программирования

Question

Мое требование, чтобы обнаружить порт не которому любое устройство связи подключено

также, как мы можем добавить драйверы любого коммуникационного устройства в корпусе, который может быть установлен вместе с установкой моего пакета

Answer 1

Option Explicit 
'****************************************************************************** 
' Description: Scans machine using the WIN32 API for all available comm hardware 
' Usage: main program calls the 'CommSettings' sub, passing the 
'   name of the communications control and a combobox name. 
'****************************************************************************** 

Dim CommCntrl    As Control         ' the communications control 
Dim cmboPort    As Control         ' combobox to populate 
Dim bNoComm    As Boolean 

Private Const MAX_COMM = 16           ' 32 max port # to check 

Private Const GENERIC_READ = &H80000000 
Private Const GENERIC_WRITE = &H40000000 
Private Const OPEN_EXISTING = 3 
Private Const FILE_FLAG_OVERLAPPED = &H40000000 
Private Const INVALID_HANDLE_VALUE = -1 

Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" _ 
            (ByVal lpFileName As String, _ 
            ByVal dwDesiredAccess As Long, _ 
            ByVal dwShareMode As Long, _ 
            ByVal lpSecurityAttributes As String, _ 
            ByVal dwCreationDisposition As Long, _ 
            ByVal dwFlagsAndAttributes As Long, _ 
            ByVal hTemplateFile As String) As Long 

Private Declare Function CloseHandle Lib "kernel32" (_ 
            ByVal hObject As Long) As Long 


Public Sub GetPorts(serialCntrl As Control, comboBox As Control) 
    '****************************************************************************** 
    ' Usage: Pass the name of the communications control, a combo box, and the 
    '   current com port setting in the calling routine. 
    '****************************************************************************** 

    Dim iCntr    As Integer         ' loop counter 
    Dim hRet    As Long          ' api return value 
    Dim sCom    As String         ' comm port name 

    On Error Resume Next 

    Set cmboPort = comboBox 

    Set CommCntrl = serialCntrl 
    Err = 0 

    cmboPort.Clear 

    ' Close the port if it's open 
    If CommCntrl.PortOpen = True Then 
     CommCntrl.PortOpen = False 
     DoEvents 
    Else 
     bNoComm = True 
    End If 

    ' Scan for all possible hardware so we can display all available ports 
    ' in the combo box. Dynamically adjusts for PC's with addin cards 
    For iCntr = 1 To MAX_COMM 
     ' try to open the port. 
     ' \\.\ required for ports > 9, works for all ports 
     sCom = "\\.\Com" & CStr(iCntr) & vbNullChar 
     hRet = CreateFile(sCom, GENERIC_READ Or _ 
           GENERIC_WRITE, 0, vbNullString, OPEN_EXISTING, _ 
          FILE_FLAG_OVERLAPPED, vbNullString) 

     If hRet <> INVALID_HANDLE_VALUE Then 
      hRet = CloseHandle(hRet) 
      cmboPort.AddItem Format$(iCntr) 
      Debug.Print iCntr 
     Else 
      ' dll error 5 = already open 
      ' dll error 2 = no harware 
      If Err.LastDllError = 5 Then 
       cmboPort.AddItem Format$(iCntr) & " - Busy" 
      End If 
     End If 
    Next 

End Sub