My First NXT “Kernel Panic”

/ 3 September 2006

Those of you that have a Mac may know what a Kernel Panic is, but for those that don’t let me explain. Our macs first boot (for a split second) to the chip firmware, the base OS for the entire mac, then that OS launches the hard disk and therefore launches the kernel, the base for Mac OS 10. From there you see the grey screen with the apple and you know from there. Sometimes this kernel unexpectedly quits, in that instance Mac OS 10 quits, along with your entire hard disk, therefore your computer is unusable unless you restart. This will be shown by the screen going opaque grey, and a multi-language message tells you to hold down the power button, thus the user end of a kernel panic. That screen, and the screenshot of Mac OS 10, are coming from the PPC or Intel chip itself. With that, I know that my NXT had a kernel panic not since the run symbol stopped (it was running a screen involved program), but since it stopped updating the ultrasonic distances. So, I quickly found a paperclip, and tore the NXT out of the machine its in to get to the restart/ memory reformat button. I had to hold down the button for 2 seconds to get the brick to restart. But, a note for those of you that this may happen to, holding it down for more than 2 seconds will result in the second function of that paperclip button, the complete reformatting of the flash drive. You’ll know if you accomplished this by turning your NXT on and instead of Lego’s logo popping up, a slow, quiet beeping sound is made. This means your NXT is on the direct AMR 7 burned-on firmware, not the generic Lego NXT OS. To restore the brick to it’s factory firmware, open the software on your computer, and choose Tools-Restore NXT Firmware, this will pop up a window showing the available firmware files, and the option to download one to your NXT. The entire download (for OS version 1.03) will take about 10 minutes not counting the re-compiling and re-downloading of your own programs. Good luck if this happens to your NXT, Alex.