accessing USB HID device

[bensonsearch]

Hi All,

This is driving me nuts, I have a DYMO postal scale which comes with USB. I wish to read the weight into my application.

The DYMO website has a app called InstaRate which can read the weight fine so it can be done. however no mention of how to.

The scale installs itself as a HID device, I have tried to find examples of how to read these but cant find anything that works (or understand it).

This code can find the device but provides no way to read as far as i can see

Imports SimpleHID
Public Class Form1
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Dim infoSetsForAllDevices = HIDManager.GetInfoSets()
        For Each sss In infoSetsForAllDevices
            ListBox1.Items.Add(sss.ProductString)
            Dim device = New HIDDevice()
            device.Init(sss.DevicePath)
        Next
    End Sub
End Class

can someone please help me figure this out? i feel im close but have reached the end of my rope

[Nightwalker83]

What are the other methods apart from Init available for device?

[bensonsearch]

the whole list (not just methods)

-Dispose
-Equals
-FeatureButtonCaps
-FeatureValueCaps
-GetHashcode
-GetType
-HidCaps
-Init
-InputButtonCaps
-InputValueCaps
-OutputButtonCaps
-OutputValueCaps
-ReadInputReport
-ReferanceEquals
-ToString
-WriteOutputReport

im assuming its got to do with writeoutputreport but it wants values that i have no idea on.......

[Nightwalker83]

Maybe it is WriteOutputReport(sss.something)?

Edit:

Not sure if Reading a Stamps.com USB Scale from C# will be of use or not? Yes, I know the code is in C# but you might see similarities between that and what you want to do.

[techgnome]

why would it be write? wouldn't it be the read method? You want to READ the scale... no?

-tg

[Nightwalker83]

why would it be write? wouldn't it be the read method? You want to READ the scale... no?

The way I look at it is that the machine allows you to load the input back in to the machine and that is where "ReadInputReport" is used.

[bensonsearch]

well that method was part of someones libaray. I saw the stamps link before but couldnt compile a dll for mike obriens libaray but got an older version and managed to, so for all out there the libaray is at: https://github.com/mikeobrien/HidLibrary and the code i used is as follows

Imports HidLibrary
Public Class Form1
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Dim inData As HidDeviceData
        Dim scale As HidDevice
        Dim weight As Decimal
        'USB\VID_0922&PID_8004
        scale = HidDevices.Enumerate(&H922, &H8004).FirstOrDefault 'VID and PID from device manager
        If scale IsNot Nothing Then
            scale.OpenDevice()
            inData = scale.Read(250)
             weight = Convert.ToDecimal(inData.Data(4)) + (Convert.ToDecimal(inData.Data(5) * 255) + Convert.ToDecimal(inData.Data(5)))
            ListBox1.Items.Add(weight)
            scale.CloseDevice()
            scale.Dispose()
        End If
    End Sub
End Class