USB HID Template for
Visual Basic 2005
Introduction
With the decline of serial and parallel
ports from modern computers, electronics hobbyists are turning more to utilizing
USB (or stick with old computers for their legacy ports). Unfortunately, unlike
serial and parallel ports, USB is far from simple and so it can be daunting to try
to develop hardware and software for it. However, there are many hardware and software
solutions that make developing USB device much simpler.
Some PIC microcontrollers now come with
a USB Serial Interface Engine (SIE) that handles the very low level parts of the
interface. However, writing firmware to work with the SIE can still be a difficult
task. Luckily, many PIC compilers come with USB libraries that work out of the box
and are dead easy to use. The code generated by these compilers tends to produce
a USB Human Interface Device (HID) as these devices do not require custom drivers
to be written because Windows has them preinstalled. However, you still need to
write your own PC software to read and write data from your USB device. This article
shows you how to do this.
Visual Basic Template
The Visual Basic template, which you can
download at the bottom of the page, generates the basic code framework that is needed
to interface with your USB device. All you need to do is set the VID, PID and buffer
sizes going into and out from the PC. After that you’re ready to read and write
data.
To give credit where credit is due, I
did not write the code that is in the template – the code is based on the code generated
by the EasyHID application from Mecanique and modified for Visual Basic 2005 by
Steve Monfette. I modified his code a little, wrote some documentation and packaged
it into a VB template.
Installing
Installing the template is simple. Download
and extract the archive and you will find two files:
USBTemplate.zip and mcHID.dll.
Copy mcHID.dll to your
windows\system32 folder and copy USBTemplate.zip
(copy the actual zip file – do not extract it) to your
My Documents\Visual Studio 2005\Templates\ProjectTemplates.
Using the Template
After installation, load up Visual Basic
2005 and create a new project. When the New
Project dialog opens, you should see the
USBTemplate option at the bottom.
Select it, give your project a name
and then click on OK. Visual Basic creates the basic code framework for you.
The following files are created and can
be found in the Solution Explorer:
1-
frmUSB:
This is the main form where USB communication takes place.
2-
mcHIDInterface:
Contains the underlying code.
3-
HOW
TO USE: Contains instructions on how to use the template.
The only file which you need to modify
is frmUSB.
Download
The template and the DLL file can be downloaded
below:
USB HID Template for Visual Basic 2005
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