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VB.net with 1216

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VB.net with 1216

Postby bartj » Thu Dec 22, 2011 6:40 pm

Hello,

I used some previously posted code but the pl1000SetInterval call returns an error number (decimal) = 16 indicating a channel error. Am using vb.net with VS2008 on XP.
Below are the api functions and the code.
Comments?

Thanks,
Bartj

Here are the api calls I am using:
Code: Select all
Declare Function pl1000OpenUnit Lib "pl1000.dll" (ByRef handle As Short) As Integer
    Declare Function pl1000CloseUnit Lib "pl1000.dll" (ByVal handle As Short) As Integer
    Declare Function pl1000GetUnitInfo Lib "pl1000.dll" (ByVal handle As Short, ByVal S As String, ByVal lth As Short, ByRef requiredSize As Short, ByVal info As Short) As Short
    Declare Function pl1000SetTrigger Lib "pl1000.dll" (ByVal handle As Short, ByVal enabled As Short, ByVal enable_auto As Short, ByVal auto_ms As Short, ByVal channel As Short, ByVal dir As Short, ByVal threshold As Short, ByVal hysterisis As Short, ByVal delay As Single) As Short
    Declare Function pl1000SetInterval Lib "pl1000.dll" (ByVal handle As Short, ByRef us_for_block As Integer, ByVal ideal_no_of_samples As Integer, ByRef channels As Short, ByVal No_of_channels As Short) As Integer
    Declare Function pl1000GetValues Lib "pl1000.dll" (ByVal handle As Short, ByVal values As Short, ByVal no_of_values As Integer, ByVal overflow As Short, ByVal triggerIndex As Integer) As Integer
    Declare Function pl1000Run Lib "pl1000.dll" (ByVal handle As Short, ByVal no_of_values As Integer, ByVal method As Short) As Short
    Declare Function pl1000Ready Lib "pl1000.dll" (ByVal handle As Short, ByRef ready As Short) As Integer
    Declare Function pl1000MaxValue Lib "pl1000.dll" (ByVal handle As Short, ByRef maxValue As Short) As Integer

Dim MAXVALUE As Integer = 4096 ' module level

And here is the code:


Sub GetPl1000()

        Dim msg As String
        Dim us_for_block As Long
        Dim triggerIndex As Long
        Dim overflow As Integer
        Dim status As Long
        Dim handle As Integer
        Dim values(200) As Integer
        Dim channels(16) As Integer
        Dim nValues As Long
        Dim ready As Integer

        ' Open device
        status = pl1000OpenUnit(handle)
        If status <> 0 Then
            MsgBox("Bad OpenUnit Call " & status)
            Exit Sub
        End If

        ' test for a valid handle
        If handle = 0 Then
            MsgBox("Invalid Handle " & status)
            Exit Sub
        End If

        'Get the maximum ADC value for this variant
        status = pl1000MaxValue(handle, MAXVALUE)
        If status <> 0 Then
            MsgBox("Bad MaxVal Call " & status)
            Exit Sub
        End If

        ' No Trigger
        status = pl1000SetTrigger(handle, False, 0, 0, 0, 0, 0, 0, 0)
        If status <> 0 Then
            MsgBox("Bad SetTrigger Call " & status)
            Exit Sub
        End If

        ' define time window, number of samples and channel we wish to use
        us_for_block = 1000
        nValues = 100
        channels(0) = 1
        channels(1) = 2

        status = pl1000SetInterval(handle, us_for_block, nValues, channels(0), 2)
        If status <> 0 Then ' !!!!status returns 16 !!!!!!!!
            MsgBox("Bad SetInterval Call " & status)
            Exit Sub
        End If

        status = pl1000Run(handle, nValues, 0)
        If status <> 0 Then
            MsgBox("Bad Run Call " & status)
            Exit Sub
        End If

        ready = 0
        Do While ready = 0
            status = pl1000Ready(handle, ready)
        Loop

        ' Get a block of 100 readings...
        status = pl1000GetValues(handle, values(0), nValues, overflow, triggerIndex)
        If status <> 0 Then
            MsgBox("Bad GetValues Call " & status)
            Exit Sub
        End If

        ' Copy the data into a string
        For i = 0 To nValues - 1
            msg = msg & "," & adc_to_mv(values(2 * i))
        Next i

        ' Close the unit when finished to drop the driver
        Call pl1000CloseUnit(handle)

        MsgBox(msg)



    End Sub
bartj
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Re: VB.net with 1216

Postby Martyn » Fri Dec 23, 2011 7:55 am

Make sure that the parameters passed to the function correctly match the API

Programmers guide
Code: Select all
pl1000SetInterval
PICO_STATUS pl1000SetInterval(
short handle,
unsigned long * us_for_block,
unsigned long ideal_no_of_samples,
short * channels,
short no_of_channels
)

Declaration
Code: Select all
Declare Function pl1000SetInterval Lib "pl1000.dll" (ByVal handle As Short, ByRef us_for_block As Integer, ByVal ideal_no_of_samples As Integer, ByRef channels As Short, ByVal No_of_channels As Short) As Integer

Local variables
Code: Select all
        Dim msg As String
        Dim us_for_block As Long
        Dim triggerIndex As Long
        Dim overflow As Integer
        Dim status As Long
        Dim handle As Integer
        Dim values(200) As Integer
        Dim channels(16) As Integer
        Dim nValues As Long
        Dim ready As Integer

Function call
Code: Select all
        status = pl1000SetInterval(handle, us_for_block, nValues, channels(0), 2)
Martyn
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Re: VB.net with 1216

Postby bartj » Fri Dec 23, 2011 4:10 pm

The code below has been corrected and works as expected. It required changes to the data types in some of the Declares and the local variables in the code.


Code: Select all
    Declare Function pl1000OpenUnit Lib "pl1000.dll" (ByRef handle As Short) As Short
    Declare Function pl1000CloseUnit Lib "pl1000.dll" (ByVal handle As Short) As Short
    Declare Function pl1000GetUnitInfo Lib "pl1000.dll" (ByVal handle As Short, ByVal S As String, ByVal lth As Short, ByRef requiredSize As Short, ByVal info As Short) As Short
    Declare Function pl1000SetTrigger Lib "pl1000.dll" (ByVal handle As Short, ByVal enabled As Short, ByVal enable_auto As Short, ByVal auto_ms As Short, ByVal channel As Short, ByVal dir As Short, ByVal threshold As Short, ByVal hysterisis As Short, ByVal delay As Single) As Short
    Declare Function pl1000SetInterval Lib "pl1000.dll" (ByVal handle As Short, ByRef us_for_block As Integer, ByVal ideal_no_of_samples As Integer, ByRef channels As Short, ByVal No_of_channels As Short) As Short
    Declare Function pl1000GetValues Lib "pl1000.dll" (ByVal handle As Short, ByRef values As Short, ByRef no_of_values As Integer, ByRef overflow As Short, ByRef triggerIndex As Integer) As Short
    Declare Function pl1000Run Lib "pl1000.dll" (ByVal handle As Short, ByVal no_of_values As Integer, ByVal method As Short) As Short
    Declare Function pl1000Ready Lib "pl1000.dll" (ByVal handle As Short, ByRef ready As Short) As Short
    Declare Function pl1000MaxValue Lib "pl1000.dll" (ByVal handle As Short, ByRef maxValue As Short) As Short



Sub GetPl1000()

        Dim msg As String
        Dim us_for_block As Integer 'integerLong
        Dim triggerIndex As Integer
        Dim overflow As Short
        Dim status As Short
        Dim handle As Integer
        Dim values(200) As Short
        Dim channels(16) As Short
        Dim nValues As Integer
        Dim ready As Integer

        ' Open device
        status = pl1000OpenUnit(handle)
        If status <> 0 Then
            MsgBox("Bad OpenUnit Call " & status)
            Exit Sub
        End If

        ' test for a valid handle
        If handle = 0 Then
            MsgBox("Invalid Handle " & status)
            Exit Sub
        End If

        'Get the maximum ADC value for this variant
        status = pl1000MaxValue(handle, MAXVALUE)
        If status <> 0 Then
            MsgBox("Bad MaxVal Call " & status)
            Exit Sub
        End If

        ' No Trigger
        status = pl1000SetTrigger(handle, False, 0, 0, 0, 0, 0, 0, 0)
        If status <> 0 Then
            MsgBox("Bad SetTrigger Call " & status)
            Exit Sub
        End If

        ' define time window, number of samples and channel we wish to use
        us_for_block = 1000
        nValues = 100
        channels(0) = 1
        channels(1) = 2

        status = pl1000SetInterval(handle, us_for_block, nValues, channels(0), 2)
        If status <> 0 Then
            MsgBox("Bad SetInterval Call " & status)
            Exit Sub
        End If

        status = pl1000Run(handle, nValues, 0)
        If status <> 0 Then
            MsgBox("Bad Run Call " & status)
            Exit Sub
        End If

        ready = 0
        Do While ready = 0
            status = pl1000Ready(handle, ready)
        Loop

        ' Get a block of 100 readings...
        status = pl1000GetValues(handle, values(0), nValues, overflow, triggerIndex)
        If status <> 0 Then
            MsgBox("Bad GetValues Call " & status)
            Exit Sub
        End If

        ' Copy the data into a string
        For i = 0 To nValues - 1
            msg = msg & "," & adc_to_mv(values(2 * i))
        Next i

        ' Close the unit when finished to drop the driver
        Call pl1000CloseUnit(handle)

        MsgBox(msg)

    End Sub
bartj
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