I seem to have managed to brick a CM3 module while uploaidng software to it - how is this possible?
While I was programming a CM3 module - at about 10% I touched a "doggy" USB hub connector that interrupted the USB connection and the upload failed.
I tried to reload the software but now the module is not seen by the PC, it does not even appear in device manger - how is it possible to brick the module?
This is potentially a very serious issue (as I suspect it will be to other CM3 users) as we plan to offer future OTA software updates to customers - but if the unit can be bricked then this is an extreme concern.
There is nothing in the CM3 manual that suggests this is possible - just that the module should default to boot loader mode:-
"When initially powered on, or after the RUN pin has been held low and then released, the BCM2837
will try to access the primary SD/eMMC interface. It will then look for a file called bootcode.bin on the
primary partition (which must be FAT) to start booting the system. If it cannot access the SD/eMMC
device or the boot code cannot be found, it will fall back to waiting for boot code to be written to it over
USB; in other words, its USB port is in slave mode waiting to accept boot code from a suitable host."
How can we recover this module?