Работа с COM портами в VB????

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

Declare Function SetupComm Lib 'kernel32' (ByVal hFile As Long, ByVal dwInQueue As Long, _
                                           ByVal dwOutQueue As Long) As Long

Declare Function BuildCommDCB Lib 'kernel32' Alias 'BuildCommDCBA' (ByVal lpDef As String, lpDCB As DCB) As Long

Declare Function SetCommState Lib 'kernel32' (ByVal hCommDev As Long, lpDCB As DCB) As Long

Declare Function ReadFile Lib 'kernel32' (ByVal hFile As Long, lpBuffer As Any, _
                                          ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, _
                                          ByVal lpOverlapped As Long) As Long

Declare Function GetCommTimeouts Lib 'kernel32' (ByVal hFile As Long, lpCommTimeouts As CommTimeOuts) As Long

Declare Function SetCommTimeouts Lib 'kernel32' (ByVal hFile As Long, lpCommTimeouts As CommTimeOuts) As Long

Declare Function CloseHandle Lib 'kernel32' (ByVal hObject As Long) As Long

Type buf
b as String
End Type
 
Dim s as buf
 
IDComDev = CreateFile('COM1', GENERIC_READ, 0, 0, OPEN_EXISTING, 0, 0)
v=SetupComm(IDComDev, 1024, 128)
v=BuildCommDCB('COM1:9600,n,8,1', DCB)
v=SetCommState(IDComDev, DCB)
v=GetCommTimeouts(IDComDev, CT)          CT.ReadIntervalTimeout = MAXDWORD
CT.ReadTotalTimeoutMultiplier = 0
CT.ReadTotalTimeoutConstant = 0
v=SetCommTimeouts(IDComDev, CT)
Do While breakIt = False
v = ReadFile(IDComDev, s, 1, RetBytes, 0)
If v = 0 Then exit do
If asc(s.b) = 13 Then Exit Do
f (asc(s.b) <> 0) And (i = 1) And RetBytes = 1 Then T = T & s.b
DoEvents
Loop
i = CloseHandle(IDComDev)

Private Sub frm1Send_Click()
''имеется форма с кнопкой 'Send' и MSComm MSC
''при нажатии на кнопку на модем
''отправляется стандартная команда
MSC.CommPort = 2
MSC.Settings = '9600,N,8,1'
MSC.PortOpen = True
On Error Resume Next
MSC.Output = 'ATDT' & '1261271' & vbCr
On Error Resume Next
S = Timer
Do While Timer < S + 5
DoEvents
Loop
MSC.PortOpen = False
End Sub

Type DCB
  DCBlength As Long
  BaudRate As Long
  fBitFields As Long 
  wReserved As Integer
  XonLim As Integer
  XoffLim As Integer
  ByteSize As Byte
  Parity As Byte
  StopBits As Byte
  XonChar As Byte
  XoffChar As Byte
  ErrorChar As Byte
  EofChar As Byte
  EvtChar As Byte
  wReserved1 As Integer
End Type

Declare Function WriteFile& Lib 'kernel32' _
            (ByVal hFile As Long, lpBuffer As Any, _
            ByVal nNumberOfBytesToWrite&, _
            lpNumberOfBytesWritten&, ByVal lpOverlapped&)
Declare Function CreateFile& Lib 'kernel32' Alias 'CreateFileA' _
            (ByVal lpFileName$, ByVal dwDesiredAccess&, _
            ByVal dwShareMode&, ByVal lpSecurityAttributes&, _
            ByVal dwCreationDisposition&, ByVal dwFlagsAndAttributes&, _
            ByVal hTemplateFile&)
Declare Function CloseHandle& Lib 'kernel32' (ByVal hObject&)
 
Declare Function FlushFileBuffers& Lib 'kernel32' (ByVal hFile&)
 
Function DialNumber(PhoneNumber, CommPort As String)
  Const WAITSECONDS=5
  Dim bModemCommand(256) As Byte, ModemCommand As String
  Dim OpenPort As Long
  Dim RetVal As Long, RetBytes as Long, i as integer
  Dim StartTime
    OpenPort = CreateFile(CommPort, &HC0000000, 0, 0, 3, 0, 0)
    If OpenPort = -1 Then Exit Sub
    ModemCommand = 'ATDT' & PhoneNumber & vbCrLf
    For i = 0 To Len(ModemCommand) - 1
        bModemCommand(i) = Asc(Mid(ModemCommand, i + 1, 1))
      Next
    RetVal = WriteFile(OpenPort, bModemCommand(0), _
               Len(ModemCommand), RetBytes, 0)
    If RetVal = 0 Then GoTo Err_DialNumber
    RetVal = FlushFileBuffers(OpenPort)
    StartTime = Timer
      While Timer < StartTime + WAITSECONDS
        DoEvents
      Wend
    ModemCommand = 'ATH0' & vbCrLf
    For i = 0 To Len(ModemCommand) - 1
        bModemCommand (i) = Asc(Mid(ModemCommand, i + 1, 1))
      Next
    RetVal = WriteFile(OpenPort, bModemCommand(0), _
               Len(ModemCommand), RetBytes, 0)
    RetVal = FlushFileBuffers(OpenPort)
Err_DialNumber:
    RetVal = CloseHandle(OpenPort)
End Function
 
Буффер bModemCommand можно описать как я показывал раньше (тип buf), я там только ошибся.
Надо так (буффер должен быть фиксированной длины иначе прога будет просто вылетать):
Type buf
  b as string*1 (в этом примере b as string*256)
End Type