Using EasyHID with VBExpress 2005 (maybe .NET as well)

[mackrackit]

Thank you Steve and David.

The VB5/Express part was my hold up.

[mister_e]

Thanks guys, don't forget to post your "It's working or not" comments...

As i write it, (~24 hours later) the template have been downloaded 76 times already

Finger crossed

[Abnormal1]

Hi,
Have been playing with this and it works great.

Only thing is that I can not get hidGetVendorName and hidGetProductName to work. I get an "Attempted to read or write protected memory" error with this and i'm not sure if im doing something wrong or that theres a problem with this .net version.

Thanks
Abnormal1

[mister_e]

Yup, Yet another .NET thingy. 'Till now, i have found a way to make it work....

   Public Sub OnPlugged(ByVal pHandle As Integer)
    Dim DeviceHandle As Integer
                              ' Mister E 
    Dim VendorName As String = "         "
                               ' USB Demo
    Dim ProductName As String = "         "

    If hidGetVendorID(pHandle) = VendorID And hidGetProductID(pHandle) = ProductID Then ' Good one?
        '
        '   get the device handle
        '   =====================
        DeviceHandle = hidGetHandle(VendorID, ProductID)
        '
        '   Get the vendor and product name from the handle
        '   ===============================================
        hidGetVendorName(DeviceHandle, VendorName, 255)
        hidGetProductName(DeviceHandle, ProductName, 255)
        End If
    Label2.Text = VendorName
    label3.text = ProductName

The trick is to assign a value to VendorName and ProductName before calling hidGetVendorName and hidGetProductName. Make sure your space/blank character are at least equal to the LEN if VendorName and ProductName. Unless, it will screw up things.

VB.NET doesn't seems to have a way to determine a fixed String size...

Anyways, i've ask the question on the MSDN forum, let's see if there's a more elegant way to do it. It has to... In meantime, the above solution work.

[Abnormal1]

Thanks for that, it now works.

I expected it to be related to not using a fixed length string, however I had only tried to set the strings to Null rather than a load of spaces.

Anyway I have found that using the following is easier than counting how many time you press the spacebar

Dim VendorName As String = New String(CChar(" "), 16)

Also in the code you posted I don't think that you need to call "hidGetHandle" as you already have that in the variable "pHandle".

[mister_e]

here's a way to assign a fixed format string in dotnet

[HTML]<VBFixedString(15)> Public VendorName As String[/HTML]

you still need to load with character it so far... don't forget the Imports Sytem

Guys over there send me few links. Load of thing to learn/try with this new .NET. (marshallxxx, exception.. syntax, InteropService.. etc etc etc). Especially when dealing with API

I've also found few nice .CHM and .PDF on VB.NET and Express... RTFM sessions will begin... when i'll wake up. <hr>

EOM

[mister_e]

Amr Bekhit has modified it a little bit and added some documentation as well

USB HID Template for Visual Basic 2005
http://www.helmpcb.com/Software/USBHIDVB/USBHIDVB.aspx