STM32G491KEU3 stuck with TrustZone on? Can read data but not write

[ca]

I have just spun up some prototype boards for a project I am working on, and I am unable to program the MCU.

I am using STM32CubeProrgammer on Windows, but have also tried Linux flashing utilities such as OpenOCD. I can read data (all F) in both cases, but not erase or flash the MCU.

When attempting to connect, I can only connect if I am in "HotPlug" mode, otherwise I get an error saying "While trust zone is enabled please try connecting via HotPlug mode"

I have no idea what trustzone is but it looks like some kind of secure boot. These chips are brand new samples sent to me by ST. I reached out to ST today but haven't heard back because it is the holidays so I figured I would post here.

I checked all the option bytes but I don't think anything is set in a way that would prevent flashing, but I am also not a software developer so I'd appreciate any guidance on that.

Any ideas? Anything is helpful, even if I've tried it already in some way.

Thank you
Chase

[STOne-32]

Dear @ca ,

we have no TrustZone in STM32G4 series which is based on Cortex-M4 core , TrustZone is coming with Cortex-M33 core in series such as STM32U5,L5,H5  for instance . I assume this is a generic message shown by our STM32CubeProgrammer not able to connect to the device , so most probably a hardware issue . Is that possible to share your schematics : VDDx, Boot pin , SWD pins and NRST to do a sanity check , also it may happen a soldering issue or something like. Try to boot from internal bootloader also and send us the screenshots .

Hope it helps ,

STOne-32