# Microsoft Office Application Help - Excel Help forum > Excel Programming / VBA / Macros >  >  Tutorial - Use MSCOMM with a serial device

## systemx

Hi all,

This forum has been a great help to me in the last few months and I wanted to give something back. Although I am no Excel or VBA expert...I have learnt one heck of a lot in recent times.

I have had some major issues using MSCOMM and finding information/support on the web. So I thought I would share how I got it working on an excel worksheet to communicate with a serial device.

Thanks

Rob

----------------------------------------------------------------

First off, if you hav'nt already done so - you will need to obtain the MSCOMM32.OCX Active X library.

Start here - http://www.yes-tele.com/mscomm.html

You will need to register it. Go to command prompt and type the following -

regsvr32 C:\Windows\System\MSCOMM32.OCX

You should get a message to indicate that the control has been registered.

Then you may need to update the registry with this key -

[HKEY_CLASSES_ROOT\Licenses\4250E830-6AC2-11cf-8ADB-00AA00C00905]
@ = "kjljvjjjoquqmjjjvpqqkqmqykypoqjquoun"

As far as the registry stuff goes, I am no expert. This worked for me...and as far as I know it is legal. But if you have any concerns...or if you are not familiar with working within the registry...I would suggest doing some more research first!

Now....you should be ready to program with MSCOMM!!!

Open up a new Excel workbook. Make sure you can see the 'Control Toolbox (View>>>Toolbars>>>Control Toolbox).

Rename your worksheet 'SerialPort'.

Once you can see the toolbox- there should be a little toolbox icon. Click the icon and select 'Microsoft Communication Control' from the list.

The cursor will change, allowing you to draw a box on the worksheet. This is the control. It does not matter where you place it - as when you open the workbook this will not be visible to the user.

Once you have created the control, right-click and select 'View Code'.

You should see something like -

Private Sub MSComm1_OnComm()

End Sub

This is the 'OnComm' event and tells excel what to do when data is received from the serial port. We will come back to this later. Lets write some code to open a port up....

Insert the following into a new sub under the OnComm sub -

Sub OpenPort()

'Open the COM Port with the relevant settings

    Worksheets("SerialPort").MSComm1.CommPort = 1
    Worksheets("SerialPort").MSComm1.Settings = "9600,n,8,1"
    Worksheets("SerialPort").MSComm1.RThreshold = 1
    Worksheets("SerialPort").MSComm1.InBufferSize = 4096
    Worksheets("SerialPort").MSComm1.PortOpen = True


End Sub

The sub above will configure the port when you try and open it. 'CommPort' is the port number your device is connected to. 'Settings' are the device setting (baud rate, parity, etc) and are usually in the device documentation (you can also use the device with Hyperterminal to get these settings).

PortOpen = True tells Excel to open the port with the above settings.

RThreshold is what we are interested in here. By setting it to '1' we are telling Excel to fire the 'OnComm' code whenever data is received from the serial port.

The way I call the port open sub, is to have a worksheet onchange event. I only want the port to open when the user selects a cell in a particular column range, so I am using the following -

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

If Not Intersect(Target, Columns("A:A")) Is Nothing Then

If Target.Value = "" Then

Call OpenPort

End If
End If

Application.EnableEvents = True

End Sub

This piece of code must sit against the 'Worksheet' 'Selection Change' section. Use the dropdown boxes at the top of your VBA editor to select this.

So now, if a cell in column 'A' is selected, the port will be opened with my settings. As RThreshold is set to '1' - the OnComm code will be called whenever I try to read from the cheque reader and am in the 'A' column.

Now to tell it do something when data is received....

Go back to your OnComm make it look like -

Private Sub MSComm1_OnComm()

If Worksheets("SerialPort").MSComm1.CommEvent = comEvReceive Then
    Call GetData
End If

End Sub

The CommEvent - comEvReceive tells Excel that if data is coming in from the serial device....do something. In this case, Call sub "GetData".

Now, to create sub "GetData" that will grab the information from the device and place it in your worksheet.

The sub below is very straightforward - but will help get you started!

Private Sub GetData()

Dim MyData As String

Wokrsheets("SerialPort").MSComm1.InputLen = 0

MyData = Worksheets("SerialPort").MSComm1.Input
ActiveCell.Value = MyData

MyData = ""

Worksheets("SerialPort").MSComm1.PortOpen = False

End Sub

The 'InputLen' setting tells Excel how much data to read from the serial device. Setting it to zero tells it to keep reading until the end of the file (ie it gets all of the data). If you know your string is always going to be 10 digits...you could set this to 10. Or you may need a function to pull the characters one at a time until you get to a specific value. It all depends on the device and what you are trying to achieve....

And you are done! You should now have a very basic working script to read data from a serial device and place it into your worksheet.

I hope this helps someone....my apologies for any poor terminology/lack of clarity and any mistakes I have made. I am not using the same code myself...and there is a great deal more that you will need to learn to use MSComm effectively. It is also the first time I have put something together like this (but that's obvious :P)

Hopefully this is a start for anyone else who is struggling to get going with this.

Have fun!

Rob  :Smilie:

----------


## JimBob

Wow this is good ... will it work for data coming through USP port?

Thanks,
Jim Anderson

"systemx" wrote:

>
> Hi all,
>
> This forum has been a great help to me in the last few months and I
> wanted to give something back. Although I am no Excel or VBA expert...I
> have learnt one heck of a lot in recent times.
>
> I have had some major issues using MSCOMM and finding
> information/support on the web. So I thought I would share how I got it
> working on an excel worksheet to communicate with a serial device.
>
> Thanks
>
> Rob
>
> ----------------------------------------------------------------
>
> First off, if you hav'nt already done so - you will need to obtain the
> MSCOMM32.OCX Active X library.
>
> Start here - http://www.yes-tele.com/mscomm.html
>
> You will need to register it. Go to command prompt and type the
> following -
>
> regsvr32 C:\Windows\System\MSCOMM32.OCX
>
> You should get a message to indicate that the control has been
> registered.
>
> Then you may need to update the registry with this key -
>
> [HKEY_CLASSES_ROOT\Licenses\4250E830-6AC2-11cf-8ADB-00AA00C00905]
> @ = "kjljvjjjoquqmjjjvpqqkqmqykypoqjquoun"
>
> As far as the registry stuff goes, I am no expert. This worked for
> me...and as far as I know it is legal. But if you have any
> concerns...or if you are not familiar with working within the
> registry...I would suggest doing some more research first!
>
> Now....you should be ready to program with MSCOMM!!!
>
> Open up a new Excel workbook. Make sure you can see the 'Control
> Toolbox (View>>>Toolbars>>>Control Toolbox).
>
> Rename your worksheet 'SerialPort'.
>
> Once you can see the toolbox- there should be a little toolbox icon.
> Click the icon and select 'Microsoft Communication Control' from the
> list.
>
> The cursor will change, allowing you to draw a box on the worksheet.
> This is the control. It does not matter where you place it - as when
> you open the workbook this will not be visible to the user.
>
> Once you have created the control, right-click and select 'View Code'.
>
> You should see something like -
>
> Private Sub MSComm1_OnComm()
>
> End Sub
>
> This is the 'OnComm' event and tells excel what to do when data is
> received from the serial port. We will come back to this later. Lets
> write some code to open a port up....
>
> Insert the following into a new sub under the OnComm sub -
>
> Sub OpenPort()
>
> 'Open the COM Port with the relevant settings
>
> Worksheets("SerialPort").MSComm1.CommPort = 1
> Worksheets("SerialPort").MSComm1.Settings = "9600,n,8,1"
> Worksheets("SerialPort").MSComm1.RThreshold = 1
> Worksheets("SerialPort").MSComm1.InBufferSize = 4096
> Worksheets("SerialPort").MSComm1.PortOpen = True
>
>
> End Sub
>
> The sub above will configure the port when you try and open it.
> 'CommPort' is the port number your device is connected to. 'Settings'
> are the device setting (baud rate, parity, etc) and are usually in the
> device documentation (you can also use the device with Hyperterminal to
> get these settings).
>
> PortOpen = True tells Excel to open the port with the above settings.
>
> RThreshold is what we are interested in here. By setting it to '1' we
> are telling Excel to fire the 'OnComm' code whenever data is received
> from the serial port.
>
> The way I call the port open sub, is to have a worksheet onchange
> event. I only want the port to open when the user selects a cell in a
> particular column range, so I am using the following -
>
> Private Sub Worksheet_SelectionChange(ByVal Target As Range)
>
> If Not Intersect(Target, Columns("A:A")) Is Nothing Then
>
> If Target.Value = "" Then
>
> Call OpenPort
>
> End If
> End If
>
> Application.EnableEvents = True
>
> End Sub
>
> This piece of code must sit against the 'Worksheet' 'Selection Change'
> section. Use the dropdown boxes at the top of your VBA editor to select
> this.
>
> So now, if a cell in column 'A' is selected, the port will be opened
> with my settings. As RThreshold is set to '1' - the OnComm code will be
> called whenever I try to read from the cheque reader and am in the 'A'
> column.
>
> Now to tell it do something when data is received....
>
> Go back to your OnComm make it look like -
>
> Private Sub MSComm1_OnComm()
>
> If Worksheets("SerialPort").MSComm1.CommEvent = comEvReceive Then
> Call GetData
> End If
>
> End Sub
>
> The CommEvent - comEvReceive tells Excel that if data is coming in from
> the serial device....do something. In this case, Call sub "GetData".
>
> Now, to create sub "GetData" that will grab the information from the
> device and place it in your worksheet.
>
> The sub below is very straightforward - but will help get you started!
>
> Private Sub GetData()
>
> Dim MyData As String
>
> Wokrsheets("SerialPort").MSComm1.InputLen = 0
>
> MyData = Worksheets("SerialPort").MSComm1.Input
> ActiveCell.Value = MyData
>
> MyData = ""
>
> Worksheets("SerialPort").MSComm1.PortOpen = False
>
> End Sub
>
> The 'InputLen' setting tells Excel how much data to read from the
> serial device. Setting it to zero tells it to keep reading until the
> end of the file (ie it gets all of the data). If you know your string
> is always going to be 10 digits...you could set this to 10. Or you may
> need a function to pull the characters one at a time until you get to a
> specific value. It all depends on the device and what you are trying to
> achieve....
>
> And you are done! You should now have a very basic working script to
> read data from a serial device and place it into your worksheet.
>
> I hope this helps someone....my apologies for any poor terminology/lack
> of clarity and any mistakes I have made. I am not using the same code
> myself...and there is a great deal more that you will need to learn to
> use MSComm effectively. It is also the first time I have put something
> together like this (but that's obvious :P)
>
> Hopefully this is a start for anyone else who is struggling to get
> going with this.
>
> Have fun!
>
> Rob  :Smilie: 
>
>
> --
> systemx
> ------------------------------------------------------------------------
> systemx's Profile: http://www.excelforum.com/member.php...o&userid=29254
> View this thread: http://www.excelforum.com/showthread...hreadid=539481
>
>

----------


## douma.meriam

Hi,

First thank you for all these detailed information.
But i still have a problem: i installed MSCOMM32.OCX and registred it successefully (using cmd comands as it was shown above) and restarted my PC, but When i try to draw a box on the worksheet ('Microsoft Communication Control' ) this message is shown:Impossible to insert an object !
Could someone help me resolve this problem?
Thank you so much  :Smilie:

----------


## arlu1201

douma,

Unfortunately you need to post your question in a new thread, it's against the forum rules to post a question in the thread of another user. If you create your own thread, any advice will be tailored to your situation so you should include a description of what you've done and are trying to do.  Also, if you feel that this thread is particularly relevant to what you are trying to do, you can surely include a link to it in your new thread.

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## douma.meriam

OK done  :Smilie:

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## SatAtTheBack

I just wanted to add my thanks for this little heads-up, and especially for the registry key which actually worked for me and got rid of the invalid license message. Why on earth do M$ need to make life so difficult for us.  :Mad:

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## emrahyigit

Hi systemx,

I try using your code. A button runs this sub below. 

Sub OpenPort()

'Open the COM Port with the relevant settings

    Worksheets("SerialPort").MSComm1.CommPort = 1
    Worksheets("SerialPort").MSComm1.Settings = "9600,n,8,1"
    Worksheets("SerialPort").MSComm1.RThreshold = 1
    Worksheets("SerialPort").MSComm1.InBufferSize = 4096
    Worksheets("SerialPort").MSComm1.PortOpen = True


End Sub

But when it comes to the Worksheets("SerialPort").MSComm1.CommPort = 1 line, I have this 438 runtime error. I think I have a problem 
with the mscomm32.ocx file. But I added and registered this file into the syswow64 folder.

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## protonLeah

emrahyigit,
Unfortunately _your post does not comply with Rule 2 of our Forum_ RULES. *Do not post a question in the thread of another member -- start your own thread.* 

If you feel an existing thread is particularly relevant to your need, provide a link to the other thread in your new thread. 

Old threads are often only monitored by the original participants.  New threads not only open you up to all possible participants again, they typically get faster response, too.

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