Arduino for STM32

I bought 50 STM32L07 ICs for a small production run.
about half of the boards i've been making have been failing in one way or another.
I've been trying to eliminate potential sources, because it's getting a little silly seeing so many beautiful devices lining my rubbish bin.

I've eliminated cheap ...

Wow. What a pull. Outstanding advice.
back down to 1.3s with the i2c speed defined in.
Perfect. Thank you.

It makes sense to that the rest is in the library loading (as you said Ray), but the load time improved as it is is much less obtrusive.
Many thanks fpiSTM. As usual.

HI All.
I'm using the U8G2 library to run a little SH1106 screen on my STM32L07 variant board.
When I turn on the board, There's a boot screen to let some internals load and some values settle.
However, before the boot logo appears on the screen, there's a very uncomfortable 2.1s delay.
Peppering ...

Thanks for taking a look at it man.
After trying out various bits of scavenged code without success, I've got the example code snippets off the ST website.
Surprisingly hard to find from google. The reference manual has a phrase to search for on the ST website which opens the secret door behind the ...

I've only just realised that STM32 Cube programmer allows you to view the data from whatever memory location you like. Very useful. EEPROM address (0x08080000) is all 0s, so my suspicion that the write was going through was also wrong.
No read or write protection bits seem to be set, so, back to ...

Hi Folks,
Following on from the bug bug detailed here (https://github.com/stm32duino/Arduino_Core_STM32/issues/1016) , the example code for EEPROM read and write wont operate on the internal EEPROM, but instead on an emulated EEPROM.

The advice on the bug note says that the HAL API can be used ...

Ah, many thanks.
Apologies for the duplicate.

Is the EEPROM size something I have to set in CubeMX maybe? I can't find any reference to it, so I'm thinking that's not it.

Hi Guys,
L072CZ contains 6KB onboard EEPROM. Loving all that this chip has to offer.
https://www.st.com/content/st_com/en/products/microcontrollers-microprocessors/stm32-32-bit-arm-cortex-mcus/stm32-ultra-low-power-mcus/stm32l0-series/stm32l0x2/stm32l072cz.html#

EEPROM.Length(); is throwing out 128 ...

Ah Amazing.
Thank you both for sharing your experience.