Nuts and Volts - May 2010

■ 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.

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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.