Why does my for loop not work? - vb.net

Question

I am trying to run a small test to see if the value sent matches the value received. however, in most cases the value received seems to be one step behind!
For i As Decimal = 0 To 127
j = Hex(i)
stsResult = PCANBasic.Read(m_PcanHandle, myCANMsg, CANTimeStamp)
CANMsg = New TPCANMsg()
CANMsg.DATA = CType(Array.CreateInstance(GetType(Byte), 8), Byte())
CANMsg.ID = Convert.ToInt32(240, 16)
CANMsg.LEN = Convert.ToByte(8)
CANMsg.MSGTYPE = TPCANMessageType.PCAN_MESSAGE_STANDARD
CANMsg.DATA(3) = Convert.ToByte(10, 16)
CANMsg.DATA(4) = Convert.ToByte(j, 16)
CANMsg.DATA(5) = Convert.ToByte(99, 16)
PCANBasic.Write(m_PcanHandle, CANMsg)
ReadAnalogVal() ' Sents a request message so that the it updates the message about to be read
stsResult = PCANBasic.Read(m_PcanHandle, myCANMsg, CANTimeStamp) 'reads bus and populates var myCANMsg with the data
hiBit = Hex(myCANMsg.DATA(0))
If (stsResult <> TPCANStatus.PCAN_ERROR_QRCVEMPTY) Then
If myCANMsg.ID = 960 And hiBit = j Then
MessageBox.Show("you sent: " & j & " and Recieved: " & hiBit)
Else
MessageBox.Show("Response did NOT match output. Output:" & j & " Recieved: " & hiBit)
End If
End If
Next
CANMsg = New TPCANMsg()
CANMsg.DATA = CType(Array.CreateInstance(GetType(Byte), 8), Byte())
CANMsg.ID = Convert.ToInt32(240, 16)
CANMsg.LEN = Convert.ToByte(8)
CANMsg.MSGTYPE = TPCANMessageType.PCAN_MESSAGE_STANDARD
CANMsg.DATA(3) = Convert.ToByte(0, 16)
CANMsg.DATA(4) = Convert.ToByte(0, 16)
PCANBasic.Write(m_PcanHandle, CANMsg)
iBuffer = PCANBasic.PCAN_FILTER_OPEN
result = PCANBasic.SetValue(PCANBasic.PCAN_USBBUS1, TPCANParameter.PCAN_MESSAGE_FILTER, iBuffer, Convert.ToUInt32(Len(iBuffer)))
If result <> TPCANStatus.PCAN_ERROR_OK Then
' An error occurred, get a text describing the error and show it
'
PCANBasic.GetErrorText(result, 0, strMsg)
MessageBox.Show(strMsg.ToString)
Else
MessageBox.Show("Filter is open again")
End If
End Function
This seems to work for some cases and then most of the time it does not match, any advise would be appreciated. this is my first VB.NET application so i may be making an amateur mistake. I have looked into Multi-threading but I'm not entirely sure how to make it work in this case.
Here is more of the application:
Imports System.Text
' Inclusion of PEAK PCAN-Basic namespace
'
Imports System.Text
Inclusion of PEAK PCAN-Basic namespace
Imports Peak.Can.Basic
Imports TPCANHandle = System.UInt16
Imports TPCANBitrateFD = System.String
Imports TPCANTimestampFD = System.UInt64
Public Class Form1
Public Sub New()
' Initializes Form's component
'
InitializeComponent()
' Initializes specific components
'
InitializeBasicComponents()
End Sub
''' <summary>
''' Message Status structure used to show CAN Messages
''' in a ListView
''' </summary>
Private Class MessageStatus
Private m_Msg As TPCANMsgFD
Private m_TimeStamp As TPCANTimestampFD
Private m_oldTimeStamp As TPCANTimestampFD
Private m_iIndex As Integer
Private m_Count As Integer
Private m_bShowPeriod As Boolean
Private m_bWasChanged As Boolean
Public Sub New(ByVal canMsg As TPCANMsgFD, ByVal canTimestamp As TPCANTimestampFD, ByVal listIndex As Integer)
m_Msg = canMsg
m_TimeStamp = canTimestamp
m_oldTimeStamp = canTimestamp
m_iIndex = listIndex
m_Count = 1
m_bShowPeriod = True
m_bWasChanged = False
End Sub
Public Sub Update(ByVal canMsg As TPCANMsgFD, ByVal canTimestamp As TPCANTimestampFD)
m_Msg = canMsg
m_oldTimeStamp = m_TimeStamp
m_TimeStamp = canTimestamp
m_bWasChanged = True
m_Count += 1
End Sub
Private Function GetMsgTypeString() As String
Dim strTemp As String
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_STATUS) = TPCANMessageType.PCAN_MESSAGE_STATUS Then
Return "STATUS"
End If
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_ERRFRAME) = TPCANMessageType.PCAN_MESSAGE_ERRFRAME Then
Return "ERROR"
End If
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_EXTENDED) = TPCANMessageType.PCAN_MESSAGE_EXTENDED Then
strTemp = "EXT"
Else
strTemp = "STD"
End If
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_RTR) = TPCANMessageType.PCAN_MESSAGE_RTR Then
strTemp += "/RTR"
Else
If (m_Msg.MSGTYPE > TPCANMessageType.PCAN_MESSAGE_EXTENDED) Then
strTemp += " [ "
If ((m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_FD) = TPCANMessageType.PCAN_MESSAGE_FD) Then
strTemp += " FD"
End If
If ((m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_BRS) = TPCANMessageType.PCAN_MESSAGE_BRS) Then
strTemp += " BRS"
End If
If ((m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_ESI) = TPCANMessageType.PCAN_MESSAGE_ESI) Then
strTemp += " ESI"
End If
strTemp += " ]"
End If
End If
Return strTemp
End Function
Private Function GetIdString() As String
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_EXTENDED) = TPCANMessageType.PCAN_MESSAGE_EXTENDED Then
Return String.Format("{0:X8}h", m_Msg.ID)
Else
Return String.Format("{0:X3}h", m_Msg.ID)
End If
End Function
Private Function GetDataString() As String
Dim strTemp As String
strTemp = ""
If (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_RTR) = TPCANMessageType.PCAN_MESSAGE_RTR Then
strTemp = "Remote Request"
Else
For i As Integer = 0 To Form1.GetLengthFromDLC(m_Msg.DLC, (m_Msg.MSGTYPE And TPCANMessageType.PCAN_MESSAGE_FD) = 0) - 1
strTemp += String.Format("{0:X2} ", m_Msg.DATA(i))
Next
End If
Return strTemp
End Function
Private Function GetTimeString() As String
Dim fTime As Double
fTime = (m_TimeStamp / 1000.0R)
If m_bShowPeriod Then
fTime -= (m_oldTimeStamp / 1000.0R)
End If
Return fTime.ToString("F1")
End Function
Public ReadOnly Property CANMsg() As TPCANMsgFD
Get
Return m_Msg
End Get
End Property
Public ReadOnly Property Timestamp() As TPCANTimestampFD
Get
Return m_TimeStamp
End Get
End Property
Public ReadOnly Property Position() As Integer
Get
Return m_iIndex
End Get
End Property
Public ReadOnly Property TypeString() As String
Get
Return GetMsgTypeString()
End Get
End Property
Public ReadOnly Property IdString() As String
Get
Return GetIdString()
End Get
End Property
Public ReadOnly Property DataString() As String
Get
Return GetDataString()
End Get
End Property
Public ReadOnly Property Count() As Integer
Get
Return m_Count
End Get
End Property
Public Property ShowingPeriod() As Boolean
Get
Return m_bShowPeriod
End Get
Set(ByVal value As Boolean)
If m_bShowPeriod Xor value Then
m_bShowPeriod = value
m_bWasChanged = True
End If
End Set
End Property
Public Property MarkedAsUpdated() As Boolean
Get
Return m_bWasChanged
End Get
Set(ByVal value As Boolean)
m_bWasChanged = value
End Set
End Property
Public ReadOnly Property TimeString() As String
Get
Return GetTimeString()
End Get
End Property
End Class
''' <summary>
''' Read-Delegate Handler
''' </summary>
Private Delegate Sub ReadDelegateHandler()
''' <summary>
''' Saves the desired connection mode
''' </summary>
Private m_IsFD As Boolean
''' <summary>
''' Saves the handle of a PCAN hardware
''' </summary>
Private m_PcanHandle As TPCANHandle
''' <summary>
''' Saves the baudrate register for a conenction
''' </summary>
Private m_Baudrate As TPCANBaudrate
''' <summary>
''' Saves the type of a non-plug-and-play hardware
''' </summary>
Private m_HwType As TPCANType
''' <summary>
''' Stores the status of received messages for its display
''' </summary>
Private m_LastMsgsList As System.Collections.ArrayList
''' <summary>
''' Read Delegate for calling the function "ReadMessages"
''' </summary>
Private m_ReadDelegate As ReadDelegateHandler
''' <summary>
''' Receive-Event
''' </summary>
Private m_ReceiveEvent As System.Threading.AutoResetEvent
''' <summary>
''' Thread for message reading (using events)
''' </summary>
Private m_ReadThread As System.Threading.Thread
''' <summary>
''' Handles of the current available PCAN-Hardware
''' </summary>
Private m_HandlesArray As TPCANHandle()