AVR debugWire on Linux

Here’s a mini-howto on how to debug 8-bit AVRs with debugWire on Linux. The examples below apply to the AVR Dragon programmer and ATtiny85 microcontroller, but should work with other supported hardware as well.

NB: target must be powered off an external supply, not from the AVR Dragon! See this post.

Enter debugWire mode

$ avrdude -c dragon_isp -p attiny85 -P usb -U hfuse:w:0x9f:m

Now power-cycle the target.

Do some debugging

$ avarice -g -w -P attiny85 :4242
...
Preparing the target device for On Chip Debugging.
Waiting for connection on port 4242.

$ avr-gdb hello.elf 
...
(gdb) target remote :4242
Remote debugging using :4242
0x00000000 in __vectors ()
(gdb)

Enter ISP mode

$ avrdude -c dragon_isp -P usb -p t85
avrdude: jtagmkII_setparm(): bad response to set parameter command: RSP_FAILED
avrdude: jtagmkII_getsync(): ISP activation failed, trying debugWire
avrdude: Target prepared for ISP, signed off.
avrdude: Please restart avrdude without power-cycling the target.

Target is now temporarily in ISP mode until it is power-cycled again.

$ avrdude -c dragon_isp -P usb -p t85 -v
...
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.15s

avrdude: Device signature = 0x1e930b
avrdude: safemode: lfuse reads as 62
avrdude: safemode: hfuse reads as 9F
avrdude: safemode: efuse reads as FF
...

You can now reprogram the fuses to disable debugWire.

I have graduated!

It’s been over four months since my last post. A lot has happened since then, but most importantly: I have graduated and now proudly hold a Master’s degree in Computer Science!

Needless to say, I have been quite busy working on my thesis these past months. Titled Evolutionary Music Composition - A Quantitative Approach, it explores the use of Artificial Evolution for the automatic generation of novel music. Here are two sample melodies: “Zelda” (evolved from scratch) and “Let It Be” (inspired by The Beatles’ song).

It has been quite a journey and I can’t help but feel a bit sad that my time as a student is over. But who knows, I might return to academia one day…

Apart from graduating, I have also…

• Spent the Easter holidays in Tanzania on Safari. Photos will eventually appear on Flickr.
• Attended GECCO 2011 in Dublin, where I presented a poster related to my thesis.
• Traveled the north-western coast of Norway, camping along the way.

At the time of writing, I’m in Berlin attending The Desktop Summit 2011 :)

After that an exciting job at ARM awaits!

Alarm Clock 0.3.2 “Indicate this” released!

This release adds support for application indicators and includes various bug fixes:

• Add support for application indicators
• Countdown label for application indicator
• New status icon indicating triggered alarms

Bugs fixed:

565302 - Add countdown label (for application indicator)
610632 - Create ~/.config/autostart if it doesn’t exist
671962 - Add support for libnotify 0.7
682999 - Properly stop triggered alarms that are not playing sound
704956 - Add support for application indicators
706832 - Clicking on status icon should bring up list instead of snoozing

Please see the Alarm Clock website for details on how to get it!