Hi everyone! I'm working on STM32 MCU's. I used get always one problem, when ever a new MCU is been assembled and ready to flash at the first time. I couldn't able to communicate. Over some time of trying it's started communicating maybe later few days.

[lm.1]

This issue i used get always even at R&D or bulk production too. It's keep on coming. Please any one help me out the exact reason. Thanks in advance.

[TDK]

Probably a hardware layout issue, or an issue with how you're flashing.

[Tesla DeLorean]

They make a few thousand parts at this point, can you be a bit more specific about the "STM32" you are using.

Some of the L0 and L4 will start from ROM when the FLASH is blank, after programming you need to cycle the power as resetting alone is not sufficient.

[lm.1]

Hi clive,

Thanks for the reply.

i'm using F0 series STM32f030 and F4 series STM32f405.

Through SWD - i'm trying to debug.

[lm.1]

Hi TDK,

Thanks for the reply.

can you suggest some application note or guideline to follow up for SWD - layout design.

[waclawek.jan]

Try with a "known good" busted e.g. a Disco or Nucleo. Start with a simple "blinky" program. Use the STLink utility to write flash.

JW