Pervasive Tangibility - AVR http://kineticsandelectronics.com/taxonomy/term/33/0 en Playing with AVR Fuses, Bricked Chips, and Testing for Low Power: Some Notes http://kineticsandelectronics.com/fuses <p>My current project (not described here) requires adjusting the clock system fuse settings in some arduino '168 and '328 chips. It turns out that there are a couple of things that can go wrong if you burn the wrong clock or SPI (serial) fuses. My pile of &quot;bricked&quot; MCU's was begining to look silly, so I did two things. First I figured out how to un-brick most of the bad ones. Second, I made a thorough study of the fuse settings in the ATmega48/88/168/328 datasheets and the Arduino documentation, particularly the boards.txt file. This text is pasted in from my project's working notes.</p> <p>------------------------</p> <p>Erase bricked chip and reprogram. </p> <p>Use an Evil board with no xtal or caps, 10K pullup on RST, and a <br /> 1MHz external clock oscillator module connected to pin 9.</p> <p>I'd been trying lots of potential fixes that looked something like this, but<br /> this is the one that finally worked. The differences are the &quot;B&quot;&nbsp; [bitrate?]<br /> switch set to 3 for a high speed spi clock, and no &quot;-v&quot; switches on the command<br /> line. Avrdude may have&nbsp; a bug relating to the -v switch.</p> <p>commandline fu from <a href="http://forum.pololu.com/viewtopic.php?t=2122" title="http://forum.pololu.com/viewtopic.php?t=2122">http://forum.pololu.com/viewtopic.php?t=2122</a></p> <p>&lt;burn&gt;<br /> varmint@Ktootoo:~$ avrdude -B 3 -c avrispmkii -p m168 -P usb -e</p> <p>avrdude: AVR device initialized and ready to accept instructions</p> <p>Reading | ################################################## | 100% 0.01s</p> <p>avrdude: Device signature = 0x1e9406</p> <p>avrdude: erasing chip</p> <p>avrdude: safemode: Fuses OK</p> <p>avrdude done.&nbsp; Thank you.</p> <p>varmint@Ktootoo:~$ <br /> &lt;/burn&gt;</p> <p> CLICK&nbsp;READ&nbsp;MORE&nbsp;TO&nbsp;SEE&nbsp;THE&nbsp;REST&nbsp;OF&nbsp;THE&nbsp;POST</p> <p><a href="http://kineticsandelectronics.com/fuses" target="_blank">read more</a></p> http://kineticsandelectronics.com/fuses#comments arduino AVR avrdude bricked fuses Tue, 01 Feb 2011 00:06:04 +0000 Ed_B 151 at http://kineticsandelectronics.com