About Scott_DeltaDev

Scott_DeltaDev · 2023-09-26

I'd like to configure GCC to suppress warnings from library files - e.g. I don't want to see the -Wconversion warning in stm32f4xx.h, but I do want to see all warnings from source files that I write myself. I'm using STM32CubeIDE v1.10.1 on Windows....

Scott_DeltaDev · 2023-09-20

I have a STM32F405 with a coin cell on VBAT and I haven't been able to get the Backup SRAM or RTC to preserve contents when removing main power. The same code works fine on another board that has a STM32F407. //Works on STM32F407 - Fails on STM32F40...

Scott_DeltaDev · 2023-09-22

Jan,You were right about VDDA != VDD causing the issue. Thanks for the help!I removed the +3.0V regulator and shorted VDDA to VDD (+3.3V) and now Vbat is preserving backup SRAM as expected.

Scott_DeltaDev · 2023-09-22

Correct - pins 18/19 are VSS/VDD, not VSSA/VDDA as shown in the table (dang excel autocomplete).Funny how often these questions can be answered by reading the datasheet... Thanks for pointing me to the right spot in it! And the link you sent reinfo...

Scott_DeltaDev · 2023-09-22

@ONadr.1 - I measure no current into VBAT when VDD is off, but that may just be that the current is too low and in the noise floor of my 1 V/A current monitor. I'll work on setting up a uA-range current measurement.There's a current spike into VBAT ...

Scott_DeltaDev · 2023-09-22

@waclawek.jan - All the power pins are connected, the following table shows voltages measured on MCU pins with w/ and w/o VDD active. All VSS pins are verified connected to GND w/ an ohmmeter. There's no PDR_ON pin on this package (LQFP64). I don'...

Scott_DeltaDev · 2023-09-22

@TDK - Yes, the data is preserved across resets as long as VDD stays at 3.3V.

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Suppress compiler warnings for library files

STM32F405 - Backup SRAM not preserved

Re: STM32F405 - Backup SRAM not preserved

Re: STM32F405 - Backup SRAM not preserved

Re: STM32F405 - Backup SRAM not preserved

Re: STM32F405 - Backup SRAM not preserved

Re: STM32F405 - Backup SRAM not preserved