April
2005, Issue 177
Simple
USB Data Acquisition
Simple
data acquisition is only a project away. Bruce shows
you how to build a simple data acquisition device
around an LPC2138. The system features a simple GUI
that allows you to view graphed data instead of the
streaming serial data in a terminal emulator session.
by
Bruce M. Pride
Just
ask any of my friends, and they’ll tell you I’m definitely
an embedded system nut. I love trying out the latest
microcontrollers and chips that can breathe new life
into my designs. A couple of my current favorites are
Philips ARM-based microcontrollers and USB-to-UART bridges.
I incorporated both of these types of devices into my
last few designs and I’ve been extremely impressed with
the results.
Another
recent addition to my bag of tricks has been on the
front end of my designs. Adding simple PC graphical
user interfaces (GUI) that can communicate with my embedded
designs has put the finishing touches on them. By adding
a nice PC GUI that can communicate with the embedded
system over a serial port, you can perform things like
system setup, real-time diagnostics, and tests. Besides
these benefits, your end user or customer will have
a more professional, user-friendly interface to work
with.
After
thinking about ways to combine all of this in a single
project, I decided to build a simple USB data acquisition
project. The system collects temperature data from an
analog temperature sensor and graphs it via a PC GUI.
Everyone wants to collect data of some sort (temperature
in my case). And what better way than over USB via an
ARM-based microcontroller? Of course, taking the data
and doing something with it is also an important part
of the process, so I’ll show you a PC GUI. By the end
of the article, you’ll be able to create your own simple
USB data acquisition device. Most importantly, though,
you’ll know how to develop with an ARM-based microcontroller,
how to use a USB-to-UART bridge, and how to make a PC
GUI to tie it all together.
