DFU flashing of apps sometimes aborts, and although rare this leads to
broken devices if no boot button or serial/jtag access exists, because
the bootloader will keep trying to start a half-flashed app that then
crashes at some point.
The easiest fix that works with existing bootloaders is to prepend a
small 512 byte stub that calculcates the crc and compares it with the
crc calculated at build time, and then either starts the actual app, or
sets the dfu flag and resets. This ensures we either have a working,
running app, or end up in the bootloader, ready to flash again.
For obvious reasons this only applies to dfu apps, and not to flash
targets like the actual bootloader itself.
Change-Id: Id6df0486c8b779889d21800dc2441b3aa9af8a5f
Remove the paragraph about writing to the Free Software Foundation's
mailing address. The FSF has changed addresses in the past, and may do
so again. In 2021 this is not useful, let's rather have a bit less
boilerplate at the start of source files.
Change-Id: Ie0a3b2273383adbb3303faffd6ff96be7f4cae99
This bl updater can be flashed as app and will update the bootloader and
then
delete itself before resetting the sam3, so the device will end up in
the newly
updated dfu bootloader afterwards, without having to press the
bootloader button
or requring any other manual interaction, ready to receive a new
application image.
Building the blupdater requires a previously built dfu-flash bootloader
bin file that
will then be embedded into the app during building.
Related: OS#1704
Related: SYS5061
Change-Id: I53dea57bba790a2ab3245d9483e0ff1c8d19d5e3