IMPORTANT A rarely occuring bug has been found in the Atmel flash ROM programming API in the CPU used in production P3s, and later kits (serial numbers #2001 on). The effect of the bug is to cause some CPU configuration bytes to be corrupted during or shortly after a firmware update. This causes the CPU to boot into the internal Atmel bootloader, instead of the P3 bootloader. If your CPU has already been affected by this problem, you can force it to boot into the P3 bootloader by following the instructions in the PDF file, "P3Resurrection.pdf". We have updated the P3 bootloader to include a check and fix routine that should ensure no CPU ends up un-bootable. A patch to update your bootloader can be found on the downloads page along with instructions for installation. See: P3 Bootloader v3.3 README The update files are: P3 Bootloader v3.3 MID format or P3 Bootloader v3.3 SYX format This update is not required for pre-production P3s using the older CPU type.