no init in RAM area question

[air]

 Hello.

I am using nrf51822/SD-130/SDK-12.3 now.

In order to preserve values ​​after reset, no init was set in the IRAM area.

The setting area is Start: 0x20007B80 / size: 0x480.

 

For testing, NVIC_SystemReset() is executed at regular intervals, and the value of the relevant area is checked using RTTviewer.

The results appear different in the two circumstances.

1. Softdevice download / keil rebuild and debugging condition

 - Here, the value is preserved after reset.

2. Hex file download – made using build batch file (softdevice + application + bootloader)

 - Here, the value is erased after reset.

 - There was no special problem with the build batch file.

 - I attach my batch file.

 

I'm looking for which problem is.

Would you give me some advice?

 Thanks.

 

build_IG8008.zip

[Vidar Berg]

Hello,

Have you allocated the same ".no_init" region in both the bootloader and the application, and do you see the same if you only program the Softdevice+application without the bootloader?

Thanks,

Vidar

[air]

 Hello,

I modified the area in the *.ld file as below.

I solved it quickly thanks to your advice.

Thank you.

  /** RAM Region for bootloader. This setting is suitable when used with s110, s120, s130, s310. */
  /* RAM (rwx) :  ORIGIN = 0x20002C00, LENGTH = 0x5380 */
  /* RAM (rwx) :  ORIGIN = 0x200025e0, LENGTH = 0x59A0 ---> old area */
  RAM (rwx) :  ORIGIN = 0x200025e0, LENGTH = 0x55A0

  /** Location of non initialized RAM. Non initialized RAM is used for exchanging bond information
   *  from application to bootloader when using buttonluss DFU OTA.
   */
  /* NOINIT (rwx) :  ORIGIN = 0x20007F80, LENGTH = 0x80 --> old area */
  NOINIT (rwx) :  ORIGIN = 0x20007B80, LENGTH = 0x480

[air]

 Hello,

I want to ask more.

I made 2 FW ver using 2 RAM address map and tested Case 1 / 2.

I don’t know why the new bootloader configuration is not reflected in Case 2.

I’m reviewing and hope your help.

 

Thanks.

********************************************************************

* FW ver 1 configuration

 - application

 - bootloader

  /** RAM Region for bootloader. This setting is suitable when used with s110, s120, s130, s310. */
  /* RAM (rwx) :  ORIGIN = 0x20002C00, LENGTH = 0x5380 */
  RAM (rwx) :  ORIGIN = 0x200025e0, LENGTH = 0x59A0

  /** Location of non initialized RAM. Non initialized RAM is used for exchanging bond information
   *  from application to bootloader when using buttonluss DFU OTA.
   */
  NOINIT (rwx) :  ORIGIN = 0x20007F80, LENGTH = 0x80

* FW ver 2 configuration

 - application

 - bootloader

  /** RAM Region for bootloader. This setting is suitable when used with s110, s120, s130, s310. */
  /* RAM (rwx) :  ORIGIN = 0x20002C00, LENGTH = 0x5380 */
  RAM (rwx) :  ORIGIN = 0x200025e0, LENGTH = 0x55A0

  /** Location of non initialized RAM. Non initialized RAM is used for exchanging bond information
   *  from application to bootloader when using buttonluss DFU OTA.
   */
  NOINIT (rwx) :  ORIGIN = 0x20007B80, LENGTH = 0x480

********************************************************************

    * test *

* Case 1 : FW ver 2

1. Ver 2 writing using nrfutil.
2. Writing some data to no init RAM area
3. Ver 2 DFU
4. No init RAM area has data I wrote before DFU
5. Writing some data to no init RAM area
6. Soft reset using debugger and nrfutil with power maintained
7. No init RAM area has data I wrote before soft reset

 * Case 2 : FW Ver 1 -> ver 2

1. Ver 1 writing using nrfutil.
2. Ver 2 DFU
3. Writing some data to no init RAM area
4. Soft reset using debugger and nrfutil with power maintained
5. No init RAM area has erased

 

[air]

I attach my ld file.

secure_dfu_gcc_nrf51.ld

[Vidar Berg]

It looks like you have done it correctly. I suggest that you review the *.map file for the bootloader and application to check if there is anything overlapping with your "no init" section.