■ FIGURE 4. AVR Dragon box.
Is a Programmer a Person or a Machine?
When I’m sitting at my laptop writing code in either
the Arduino IDE or AVRStudio editors, I’m a programmer
and I’m programming. After I compile the code and
upload it to the AVR, I use a programmer for programming
the IC. So, yes, there is a bit of confusion with the words
programmer and programming. From one view, it is a
human activity and from another it is a machine activity.
We will see how to use an Atmel AVR Dragon as our
hardware programmer. If you can get your hands on an
AVRISP or an STK-500, there is no need to get a Dragon
since both will do ISP programming just as well.
AVR Dragon
I’ve got to admit that the AVR Dragon provides the best
out-of-box experience I’ve ever had with a programmer —
mainly because the box is so darn cool (Figures 4 and 5).
The cover has a Norwegian and a Chinese Dragon biting
each other’s tail. (There just has to be an interesting story
behind that.) Unfortunately, once you get it out of the
box, the trouble starts. Don’t get me wrong, this is a great
little board and very economical, but you’ve got to do some
serious homework to use all its features. Plus, you need to
purchase additional parts to make it do anything. Neither
the jumpers nor the socket shown in Figure 6 come with
■ FIGURE 6. Dragon
with jumpers.
72
May 2010
■ FIGURE 5. AVR Dragon out of the box.
the Dragon. That shouldn’t be considered a fault since
these items would raise the cost and frankly, anyone using
the Dragon should already know how to acquire and use
the extras. One warning: Do not touch this board when it
is powered. Some earlier Dragons failed when touched,
and while the problem is supposed to be fixed, why on
earth would you want to touch a powered-up board,
anyway? Just keep your hands to yourself mister!
Dragon Rider
Frankly, the Dragon — while economical — is a bear
for the novice to set up. You will need various jumper
wires, cables, and sockets that don’t come with the board.
One really good solution to this problem is to get the
Dragon Rider kit from www.ecrostech.com as shown in
Figure 7. This solution more or less turns the Dragon into
an STK-500 but with USB and an LCD, so it is well worth
considering.
Dragons, Medusas, and BeAVRs?
We will use the Dragon to put the bootloader on the
■ FIGURE 7. Ecrostech Dragon Rider.
(Photo used with permission of Graham Davies of Ecrostech).