--ramwr values persist after reboot (using nrfjprog to set values)

[rshankle]

Hi All,

I have an application running on the nRF52832.   From within the application I can store data to 0x2000 2010 - 0x2000 2028  and read the data back after a reboot/power cycle with no problem after I implemented the following code in my save_state():

#if defined(NRF52832_XXAA) || defined(NRF51422) || defined(NRF51822)
     NRF_POWER->RAMON |= (POWER_RAMON_OFFRAM0_RAM0On << POWER_RAMON_OFFRAM0_Pos) |
     (POWER_RAMON_OFFRAM1_RAM1On << POWER_RAMON_OFFRAM1_Pos);
#endif

What I'm trying to do now is program multiple devices using nrfjprog,  which works well, but when I write to these memory locations the data is only good for the first run.  If I cycle power to the board it doesn't remember the values I wrote using nrfjprog --ramwr   (or --memwr)    I even do --verify to confirm the write.

Is there an nrfjprog command I need to give that is similar to my RAMON code above?

thanks much!
Bob

[Håkon Alseth]

Hi,

 

There are three types of reset which does not reset the RAM, as shown in this table:

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/power.html?cp=3_1_0_17_7#unique_832471788

 

A soft-reset is one of the sources that doesn't reset the RAM, and therefore the stored data still persists. A power cycle will include a power-on-reset, thus you cannot trust your RAM content at that point. 

 

Kind regards,

Håkon

[rshankle]

Hi,

Using nrfjprog how do I write to NonVolatile RAM so the data persists after I power the board off and back on?

(A different way to look at it, how do I get data to persist after doing "nrfjprog --pinreset"  ?

thanks,
Bob

[Håkon Alseth]

Hi,

 

Could you try "nrfjprog --reset"?

 

Kind regards,

Håkon

[rshankle]

Hakon,

I need to program the configuration parameters into the nRF52832 and then power down the board for shipping to the customer's site.

I've tried "nrfjprog --reset"  that of course works because power isn't lost to the board.  But "nrfjprog --pinreset" doesn't work (meaning the data isn't maintained in memory when the processor comes back up.)

Are there registers/memory locations in the nRF52832 that I can use as NVRam? 

thanks,
Bob

[Håkon Alseth]

I do not see any other solutions than storing these settings to the flash.

You can look at "fds" module (which uses fstorage) for flash storage.

 

Kind regards,

Håkon