2022-12-29 04:37 AM
I have initialized variable as below
uint8_t u8Flag1ForStoreVer __attribute__ ((section (".RAM1_region")));
So, after soft reset I am getting data back.
But also same I am getting after hard reset(Power cycle) , even aftre long time
What should be value in RAM after power on ?
I am using STM32WL controller.
2022-12-29 04:58 AM
Indeterminate
2022-12-29 05:09 AM
can we make it zero (Only incase power on) ?
And also in my case mostly I am getting same value not Indeterminate .
2022-12-29 06:24 AM
> can we make it zero
by writing your own software.
> And also in my case mostly I am getting same value not Indeterminate .
There is no guarantee for any specific (deterministic) content and no physical "reset" line in a typical SRAM cell.
hth
KnarfB
2022-12-29 10:23 AM
I think "frequently the same" fits within the venn diagram I'm drawing.
Perhaps there is significant bulk capacitance in the design, and very low current draw?
I would perhaps look at the RTC or wakeup/standby related status bit. Not an active user of the STM32WL family
Perhaps there's some RAM area cleared via TAMPER ?
2022-12-29 10:32 AM
Is a battery / super-cap used in the design?
2022-12-29 08:01 PM
No
2022-12-29 08:02 PM
I have tried to write zero on respective address and I am getting that.
But after power on/off , I am still getting default previous value
2022-12-29 09:48 PM
Controller can supplied parasitic through the protection diodes of the GPIOs from stlink/jlink, if connected.
2022-12-29 10:15 PM
No its not connected