by Jon Williams
Putting the Spotlight on BASIC Stamp Projects, Hints, and Tips
GUI on a Beam of IR
Wireless doesn't always mean RF ...
If you ask my close friends, they’ll tell you that I’m as
stubborn as a mule, yet I maintain the right to be
human; therefore, the right to be wrong. I’d like to
think that, when I am wrong, I admit it — I try, anyway.
When the FlexiPanel first came out a few months
ago I looked at it — for about two seconds — and
thought it was wholly uninteresting. It turns out I was
wrong; it’s actually a very clever device. I think what
originally put me off was that I assumed I’d have to
develop a GUI for my Pocket PC with traditional tools.
While that’s not too hard, it’s certainly not as easy as
developing a desktop application. This is especially
true when one needs to access serial communications
ports (this includes IR). Well, again, I was wrong because
I just didn’t give the FlexiPanel a fair look the first time
through. Let me correct that.
Beam Me Up, GUI
NUTS & VOLTS
It turns out that we don’t have to develop software
for our Pocket PC after all — that’s already been
done for us in the form of the FlexiPanel client
software (called VCP for Virtual Control Panel). So what
gives? Well, here’s what I didn’t originally understand: The
VCP acts like a specialized browser for the FlexiPanel
GUI to the
VCP that runs
on our Pocket
and a very
means is that
we could have
Figure 1. VCP in Windows.
devices using FlexiPanel modules and not have to worry
about separate apps for each one on our Pocket PC.
Imagine what a hassle the Internet would be if we needed
a separate application for every website we visited.
In fact, the workflow to use the FlexiPanel is about
the same as that for creating and publishing a website
on the Internet. The first step isto create a script file
that will produce the desired output in the browser
application. That file is uploaded tothe server — in our
case, to the FlexiPanel module. A client request will cause
the file to be downloaded anddisplayed to the client.
Sophisticated web pages will allow the user to provide
information to the server through the interface; so does
the FlexiPanel VCP.
So, where does the BASIC Stamp microcontroller
fit in? Its purpose is to serve as the host for the FlexiPanel
module. As the host, it can send information to the
module that can be displayed in the VCP and it can also
read information from the module (that was provided by
the VCP) and is required by its application.
Man, It’s Hot!
Summers in North Texas are hot and humid —
there’s no getting around it. That being the case (and the
temperature on my mind), let’s demonstrate the
FlexiPanel system by creating a handheld UI for an air
conditioning controller. I used my own home AC
controller as the model for the project. Here are the
• Display current temperature
• Display current status
• Set/Display temperature setpoint
• Set/Display operating mode
• Set/Display fan mode
Application logic and control outputs are provided by
the BASIC Stamp. It also reads the current
temperature from the DS1621 (I2C version of our old
friend the DS1620). Since we’re using the VCP, we don’t
have a local display — but we could add one later if we
choose to, since there are plenty of I/O
pins left when we’re done with this project.