new STM32L431 chip first time running failed

[dmaST]

Hello,

 

When programming an ELF file into a new STM32L431 chip(blank FLASH) for the very first time, the program does not start running automatically. It only runs correctly after a full power-off reset.

However, after this initial procedure, new ELF files can be programmed and executed directly without requiring a power-off reset.

What could be causing this issue? I recall that the STM32G0 series had a similar problem.

**Additional details:**
- BOOT0 is connected to ground via a 1M ohm resistor.
- The STLINK V3 MiniE Vtarget is connected to the board’s 3.3V supply.
- OB setting is not touched.

 

Thanks!

[Uwe Bonnes]

Probably the "Flash empty" bit is only reset on power on reset.

[dmaST]

Thanks.

then, it's normal?

[Uwe Bonnes]

1 MOhm for boot pull down is also very high. Try with <= 10 k.

[Tesla DeLorean]

A lot of the parts latch BOOTx or ROM/FLASH mapping at initial power up, mainly those actively detecting blank memory and running the System Loader in the blank case. Usually it's about latching Option Bytes, and protection against exploits there.

Check bits also in FLASH->SR, PEMPTY?