Posted on May 17, 2011 at 12:30> if erase or download are atempted by the loader the uP seems to jump out of boot mode and back into the programme that is already onboard
> a current spike ... during flash programming could trigger the BOR. but then why is it reading BOOT0 as low?
> The idea of the push button is that it is held down during reset
that explains it, now you can be almost sure that a reset is being triggered, and only when erasing or programming the flash, not when reading it. I keep thinking that the most probably cause is a BOR, secondary to a supply problem. I recommend that you check *again* that all supply pins (analog, battery, etc) are connected according to the ref manual recommendations. even low quality bypass capacitors could conceivably be the cause.
> could you try the new v1.1 -alpha ... ?
> this intially worked, i was able to erase one uP
the new PC software has different timing and can trigger the problem at different times.
(the other option is that you're reseting the chip yourself with a noisy reset signal or somthing. BTW, the flash loader doesn't enable the external oscillators at all.)
