B-L072Z-LRWAN1 don't run with external power

[mise]

Hi,

the program does not start if I connect a second usb power supply (or external power supply). The MCU runs normally when a st-link is connected. I tried a simple program - LED blink. The voltage on the MCU is good and the power LD6 is on. Any fuse or lock?

Thank you

[Tesla DeLorean]

Make sure you have current ST-LINK firmware, and that NRST is not being held low.

[mise]

ST link FW is new V2.33.25 now and NRST is high. It runs normally if both power are connected. The program will stop if I disconnect the st-link. The LED stays on (only stop - no reset).

[Tesla DeLorean]

What are you configuring as a clock source? 8MHz HSE?

[mise]

I use internal HSI 16 MHz. The board has no soldered external crystal

[Tesla DeLorean]

The ST-LINK supplies an 8 MHz signal, the Murata has an 32 MHz TCXO

Run these things from batteries here. Check jumper settings.

Perhaps output diagnostics via a UART so you better understand what's happening internally.

[mise]

ok, I'll try to find something

Thank you