I noticed the reset pin gives a periodic pulse when the chip has never been flashed.
Is this a normal behaviour?
Certainly! The 'invalid' PC/SP startup-values fetched from blank Flash memory quickly lead to 'nested hard faults', and the default power-on behavior for that condition ends in a hard reset, which starts the process all over again.
thank you for your answer!
we have a problem, when the microcontroller has never been flashed, if the external watchdog timer is connected, we don't manage to flash it (using JTAG)
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