(08-27-2018 12:16 PM)cyrille de brébisson Wrote: Hello,
Actually, you could brick a G2.
The only thing to do to do so is to correctly write "bad" data in the code part of the flash.
At this point, the bootloader would load incorrect code in RAM and start execute it.
If the "modified" code is in a rarely, or non critical part of the system (a rarely used CAS fuction for example), you will still be able to use the calcualtor and update it...
But if the corruption correspond to an OS part, or a driver, then the calcualtor will crash on boot all the time 
This requires writing data correctly to the flash (every flash sector has ECC in it), which would be hard to do for a user, only a very serious system bug is likely to cause this type of problems...
Should the flash become "simply" corrupted (beyond ECC capacity to repare), then the bootloader is supposed to load the 2nd SW image, which is the "HP" bootlaoder and will request an update.
Should all load fails, then the NXP ROM based bootloader will take over and be detected by the con kit which will update the calculator.
In the case of a trully bricked unit (bad data correctly programmed in flash), there is still a way out.
Open the calcualtor and reboot it while shorting 2 data pin of the flash chip. This will cause every flash read to fail ECC and force the NXP bootloader to take control. At this point, you can update the calcualtor.
This happened to me a couple of times during development.
Cyrille
Are you sure that that's all?
No JTAG type re-flashing?
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