STM32 Unable to get Core ID

[Najistics101]

Hi All,

I'm new to using the STM32 and honestly had great grief trying to connect to the chip.

I'm using STlink V3 and designed my own PCB.

Trying to flash a F/W to the PCB. 

I ordered the PCB from JLCPCB.

I keep getting unable to get core ID as a message and I can't figure out why?

I seem to be able to connect for a few seconds but than i get a message, unable to get core ID and it disconnects.

When I compile a code and try to flash it, it also tells me flash successful but I don't think the code got flashed successfully as the chip doesn't work as expected and also I am still unable to connect to it and i get messages unable to get Core ID.

Any help or suggestions? I have the RST connected to GND with a resistor, schematics attached.

[TDK]

> When I compile a code and try to flash it, it also tells me flash successful but I don't think the code got flashed successfully as the chip doesn't work as expected

If it says successful, it was probably successful. "doesn't work as expected" is probably a code bug. What does your code do? Keep it simple, blink an LED as a first test.

Run it in debug mode, step through, etc.

Schematic seems okay.

> I have the RST connected to GND with a resistor

Guessing this is a typo. A 1 nF cap to GND is fine.

[Najistics101]

Thanks for your reply. 
I was under the same impression as you.

But using STM32CubeProgrammer i can never fully connect  to the STM32 in the new PCBs.

It keeps telling me unable to get core ID.

Any idea why?

[Karl Yamashita]

Try removing R62 and see if it improves

[TDK]

If you cannot connect, what is telling you the flash was successful?

Could be a board manufacturing issue. Bad solder joint. Wrong orientation. No or insufficient power. Rather than guess, be objective about it.

[Najistics101]

would this play any affect? 

The Schematic design is created using STM best guidelines.
Also why am i able to flash a firmware at times and not be able to connect to the chip? 

[Najistics101]

"If you cannot connect, what is telling you the flash was successful?" i'm wondering the same exact thing.

I got the PCB made at JLCPCB, the chip has sufficient power. If it's wrong orientation i would not be able to connect not even for a few seconds and i would not be able to flash any firmware successfully using STM32cubeIDE

[Karl Yamashita]

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I got the PCB made at JLCPCB, the chip has sufficient power. 

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What is sufficient power supposed to mean? Are you 100% sure that Vdd is supplied to the STM32? If the STM32 does not have Vdd, STM32CubeProgrammer will complain about not getting the core ID.

Copy and paste the exact errors you're getting as there has to be more than just than one message.. 

[Najistics101]

Is there a BOOT0 that i need to connect to ground? 
Do you know which pin this is looking at my schematics?