Comms Problem

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Aug 7th, 2012, 03:42 PM
sbarber007

Comms Problem

Hi All

I am sending 13 characters to my vb6 prog via comms which works most of the time but then for some reason the 13th character becomes the first character and it does this all the time until i reload my vb6 program example:-
1907122220870 is how it should be but ends up like 0190712222087 help would be very greatful

Code:

Private Sub Form_Load() Dim textfile As String Open "C:\users\administrator\dirnames.txt" For Input As #1 Do While Not EOF(1) Input #1, textfile FolderCreator.Combo1.AddItem (textfile) Loop Close #1 ' Show Date on main screen. 'Label3.Caption = DateValue(Now) ' Fire Rx Event Every Two Bytes MSComm1.RThreshold = 13 ' When Inputting Data, Input 2 Bytes at a time MSComm1.InputLen = 13 ' 9600 Baud, No Parity, 8 Data Bits, 1 Stop Bit MSComm1.Settings = "9600,N,8,1" ' Disable DTR MSComm1.DTREnable = False ' Open COM1 MSComm1.CommPort = 1 MSComm1.PortOpen = True MSComm1.InBufferCount = 0 End Sub Private Sub MSComm1_OnComm() Dim sData As String ' Holds our incoming data Dim lHighByte As Long ' Holds HighByte value Dim lLowByte As Long ' Holds LowByte value Dim lWord As Long ' Holds the Word result ' If comEvReceive Event then get data and display If MSComm1.CommEvent = comEvReceive Then ' Shell ("subst Z: /D") 'Shell ("net use /Delete Z:") sData = MSComm1.Input ' Get data (5 bytes) ' lHighByte = Asc(Mid$(sData, 1, 1)) ' get 1st byte ' lLowByte = Asc(Mid$(sData, 2, 1)) ' Get 2nd byte ' Combine bytes into a word ' lWord = (lHighByte * &H100) Or lLowByte ' Convert value to a string and display ' lblRCTime.Caption = sData ' MkDir sData ' Dim folder As String, filename As String, path As String Label8.Caption = sData 'MSComm1.Output = sData Dim wshThisShell As WshShell Dim lngRet As Long Dim strShellCommand As String Dim strBatchPath As String 'label8.caption = "" Set wshThisShell = New WshShell strBatchPath = "c:\deletevert.bat" 'the path for the batch file you're using strShellCommand = """" & strBatchPath & """" 'the ridiculous number of quotation marks is necessary 'when there is a space in one or more of the folder names lngRet = wshThisShell.Run(strShellCommand, vbNormalFocus, vbTrue) 'set 3rd argument above to vbFalse for asynchronous 'execution of the batch file. 'label8.caption = "" 'label9.caption = "" If Dir$("e:\" & sData, vbDirectory) = "" Then Label9.Caption = "Directory does not exist." MkDir "e:\" & sData MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(0) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(1) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(2) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(3) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(4) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(5) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(6) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(7) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(8) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(9) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(10) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(11) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(12) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(13) MkDir "e:\" & sData & "\" & FolderCreator.Combo1.List(14) 'Shell ("subst F: " & "e:\" & sData) Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & sData & " /persistent:yes") Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & sData & " /persistent:yes") MSComm1.Output = sData

Regards
Steve
Aug 7th, 2012, 05:08 PM
DataMiser

Re: Comms Problem

Why would you think you would get 5 bytes of data here?

Code:

sData = MSComm1.Input ' Get data (5 bytes)

You have your threshold set to 13 so the event will not fire until 13 bytes are present in the buffer.
Input would read all bytes in the buffer unless maybe if you have your sData string defined as a fixed length of 5 in which case you would run into problems due to the fact that 13 is not evenly divisible by 5

Quote:

strShellCommand = """" & strBatchPath & """"
'the ridiculous number of quotation marks is necessary

You can optionally do it like this

Code:

strShellCommand = CHR$(34) & strBatchPath & CHR$(34)

As for your issue I can't tell what you are really trying to do
Aug 8th, 2012, 01:35 AM
Doogle

Re: Comms Problem

Also, the RTHreshold Property value is the minimum number of bytes that must be in the MSComm internal buffer before the OnComm event triggers. By the time it does trigger, there may be more than RTHreshold bytes in the buffer which you will then read.

I find it 'safer' to set RTHreshold to 1 and buffer the input until the end of the record is reached (in your case, until you have at least 13 bytes in the buffer)

Code:

Private Sub MSComm_OnComm() ' ' Assumes RTHreshold Property is set to a value > 0 ' (Recommended value is 1) ' Static strBuffer As String Dim strData As String Dim strRX As String Dim boComplete As Boolean Select Case MSComm.CommEvent Case comEvReceive strData = MSComm.Input strBuffer = strBuffer & strData Do If Len(strBuffer) >= 13 Then strRX = Mid$(strBuffer, 1, 13) ' ' rest of your code goes here - strRX contains the 13 characters sent ' After you've done all your processing add the following code ' If Len(strBuffer) = 13 Then strBuffer = "" boComplete = True Else strBuffer = Mid$(strBuffer, 14) End If Else boComplete = True End If Loop Until boComplete = True End Select End Sub
Aug 8th, 2012, 07:57 AM
DataMiser

Re: Comms Problem

Yep, That's the way I would do it too.
Aug 8th, 2012, 04:09 PM
sbarber007

Re: Comms Problem

Hi Thanks For all your replays

@doogle

Basicly what my program does is creates folders and and then creates a virtual drive from infomation from the comms "engine numbers", I have the comms open all the time waiting for 13 numbers to be sent then it creates a folder with the 13 numbers, another software then saves images to the virutal drive then another engines comes in to station and then another 13 unquie number is sent then creates folders and so on for each engine.

Could you please check though this script below I have inserted with your script Thanks

I dont understand the strBuffer = Mid$(strBuffer, 14)
what is the 14 value, and what does boolean and bocomplete do.

Private Sub Form_Load()
Dim textfile As String

Open "C:\users\administrator\dirnames.txt" For Input As #1
Do While Not EOF(1)
Input #1, textfile
FolderCreator.Combo1.AddItem (textfile)
Loop
Close #1

' Show Date on main screen.
'Label3.Caption = DateValue(Now)

' Fire Rx Event Every Two Bytes
MSComm1.RThreshold = 1 ' Is this correct
' When Inputting Data, Input 2 Bytes at a time
MSComm1.InputLen = 13 ' Is this correct

' 9600 Baud, No Parity, 8 Data Bits, 1 Stop Bit
MSComm1.Settings = "9600,N,8,1"
' Disable DTR
MSComm1.DTREnable = False

' Open COM1
MSComm1.CommPort = 1
MSComm1.PortOpen = True
MSComm1.InBufferCount = 0 ' Do I need this
End Sub

Private Sub MSComm1_OnComm()

'
' Assumes RTHreshold Property is set to a value > 0
' (Recommended value is 1)
'
Static strBuffer As String
Dim strData As String
Dim strRX As String
Dim boComplete As Boolean
Select Case MSComm1.CommEvent
Case comEvReceive
strData = MSComm1.Input
strBuffer = strBuffer & strData
Do
If Len(strBuffer) >= 13 Then
strRX = Mid$(strBuffer, 1, 13)
'
' rest of your code goes here - strRX contains the 13 characters sent
' After you've done all your processing add the following code

' START OF MY SCRIPT

Label8.Caption = strData
'MSComm1.Output = strData
Dim wshThisShell As WshShell
Dim lngRet As Long
Dim strShellCommand As String
Dim strBatchPath As String
'label8.caption = ""
Set wshThisShell = New WshShell
strBatchPath = "c:\deletevert.bat"
'the path for the batch file you're using
strShellCommand = Chr$(34) & strBatchPath & Chr$(34)
'the ridiculous number of quotation marks is necessary
'when there is a space in one or more of the folder names
lngRet = wshThisShell.Run(strShellCommand, vbNormalFocus, vbTrue)
'set 3rd argument above to vbFalse for asynchronous
'execution of the batch file.
'label8.caption = ""
'label9.caption = ""
If Dir$("e:\" & strData, vbDirectory) = "" Then

Label9.Caption = "Directory does not exist."
MkDir "e:\" & strData
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(0)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(1)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(2)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(3)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(4)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(5)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(6)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(7)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(8)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(9)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(10)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(11)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(12)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(13)
MkDir "e:\" & strData & "\" & FolderCreator.Combo1.List(14)

Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & strData & " /persistent:yes")
Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & strData & " /persistent:yes")
MSComm1.Output = strData

Else

ViewRejects.ViewList.AddItem strData & " REJECTED ON " & Now
Label5.Caption = ViewRejects.ViewList.ListCount
Label9.Caption = "Directory exists."
Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & strData & " /persistent:yes")
Shell ("net use Z: " & "\\ENDOFLINE\STORAGE\" & strData & " /persistent:yes")
MSComm1.Output = strData

Open "e:\REJECTS.txt" For Append As #1
' For I = 0 To Lis't1.ListCount - 1
Print #1, strData & " REJECTED ON " & Now
' Next
Close #1

Open "e:\" & strData & "\REJECTS.txt" For Append As #2
' For I = 0 To Lis't1.ListCount - 1
Print #2, strData & " REJECTED ON " & Now
' Next
Close #2
End If
End If
' THE REST OF YOUR SCRIPT got compile error below

If Len(strBuffer) = 13 Then
strBuffer = ""
boComplete = True
Else
strBuffer = Mid$(strBuffer, 14)
End If
Else ' I get Compile Error Else Without IF
boComplete = True
End If
Loop Until boComplete = True
End Select
End Sub

Thanks for your help

Regards
Steve
Aug 8th, 2012, 07:52 PM
DataMiser

Re: Comms Problem

You added to many End IFs

Code:

' Next Close #2 End If End If ' this is the cause of your error ' THE REST OF YOUR SCRIPT got compile error below If Len(strBuffer) = 13 Then
Aug 9th, 2012, 02:52 AM
Doogle

Re: Comms Problem

Quote:

Originally Posted by sbarber007

I dont understand the strBuffer = Mid$(strBuffer, 14)
what is the 14 value, and what does boolean and bocomplete do.

After you've processed the 13 bytes in the buffer you need to check whether there were any more in there. (you might have actually read more than 13 bytes) If there are then that statement moves the remaining data to the front of the buffer. ie Byte number 14 to the end of strBuffer

The Boolean Data Type has two possible values "True" and "False" (where "False" has a value of 0 and "True" is 'Not False' )

boComplete is used to signal when to exit the Do Loop; there are two conditions when it will exit (a) When the data has been processed and there's nothing left in the buffer and (b) When there is less than 13 bytes in the buffer.