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Reading Data from Serial Port

Reading Data from Serial Port

Reading Data from Serial Port


I'm pretty new at VB and programming in general, but I don't think my question is too hard of one.

I want to be able to receive data from a serial port and write that data to a text file until I either tell it to stop or the connection is gone.  Now I've never programmed anything to read data from an outside source so this is new ground for me.

So, any help as far as structure and code goes would be greatly appreciated.  


RE: Reading Data from Serial Port

Here is the code I have so far....unfortunately I don't have anything to test this code with (nothing in serial port).  I've put the MSComm object into the form...so I guess my question now is...to the best of your knowledge, will this work for the above described situation?

Private Sub cmdClose_Click()
    MSComm1.PortOpen = False
    lblStatus.Caption = "Closed"
    lblStatus.ForeColor = &HFF&
End Sub

Private Sub cmdOpen_Click()
    MSComm1.CommPort = 1
    MSComm1.Settings = "9600,N,8,1"
    MSComm1.PortOpen = True
    lblStatus.Caption = "Open"
    lblStatus.ForeColor = &HC000&
End Sub

Private Sub cmdReceive_Click()
Dim Data As Variant
    Loop Until MSComm1.InBufferCount > 0
    Data = MSComm1.Input
    Open "C:\Data.txt" For Append As #1
    Write #1, Data
    Close #1
End Sub

RE: Reading Data from Serial Port

Ooops  the Receive button code is wrong   it should read the following  (I think?):

Private Sub cmdReceive_Click()
Dim Data As Variant

    Data = MSComm1.Input
    Open "C:\Data.txt" For Append As #1
    Write #1, Data
    Close #1
    Loop Until MSComm1.InBufferCount = 0  'As long as there is data in the buffer OR  Returns 0 if user clicks "Close Port"
End Sub

RE: Reading Data from Serial Port

It seems to be correct.

Can you test it with a null modem and a laptop?

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