Soft device 7.2.0 Flash and RAM configuration

RE: Soft device 7.2.0 Flash and RAM configuration

Vidar Berg — Thu, 15 Apr 2021 09:23:14 GMT

Thanks for the update. Yes, this define should have been part of the config setup, and not a hardcoded setting in the source file as the required stack size is application depentent. This has been reported internally.

RE: Soft device 7.2.0 Flash and RAM configuration

DaveC — Thu, 15 Apr 2021 09:12:51 GMT

We think we found the issue. It seems that when using SDK 17.0.2 (Soft Device 7.2.0) we have to increase the value of #define:

#define NRF_BLE_FREERTOS_SDH_TASK_STACK 256 in file nrf_sdh_freertos.c

This is a hard coded define within the Nordic SDK. We have provisionally double it to 512 and the FreeRtos stack overflow exception is no longer thrown (a smaller value could also work)

Q1) As this is a hard coded value within the SDK should it not just work "out of the box"

Q2) If the value has to be modified per application should it not be part of the Config setup?

RE: Soft device 7.2.0 Flash and RAM configuration

Vidar Berg — Wed, 07 Apr 2021 10:13:17 GMT

Maybe some of the updated modules (SDK or Freertos) has lead to a slight increase in stack usage? As far as I can tell, the vApplicationStackOverflowHook() function should not get called unless you actaully have a stack overflow in one of the threads.

RE: Soft device 7.2.0 Flash and RAM configuration

DaveC — Tue, 06 Apr 2021 14:01:20 GMT

Thanks for the reply. I'm updating from an older sdk/soft device to 7.2.0. The freertos settings have not changed for the application. They work fine when I use the same ap/freertos with the old sdk/soft device (6.1.1)

RE: Soft device 7.2.0 Flash and RAM configuration

Vidar Berg — Tue, 06 Apr 2021 13:22:30 GMT

Hello,

Sorry for the delayed response. The linker script looks to be correct now, but I'm not sure why the vApplicationStackOverflowHook() becomes invoked. Have you tried to increases the stack sizes in all of your Freertos tasks? I would also try to increase the stack for the Softdevice task (NRF_BLE_FREERTOS_SDH_TASK_STACK). It's only 256 bytes by default, which may be a bit low depending on the application.

RE: Soft device 7.2.0 Flash and RAM configuration

DaveC — Thu, 01 Apr 2021 10:58:24 GMT

So with this Configuration I get an error when calling nrf_sdh_enable(..) as above:

MEMORY
{
FLASH (rx) : ORIGIN = 0x27000, LENGTH = 0xD9000
RAM (rwx) : ORIGIN = 0x200016FC, LENGTH = 0x38000
}

And with this configuration Free Rtos generates a vApplicationStackOverflowHook() error

MEMORY
{
FLASH (rx) : ORIGIN = 0x27000, LENGTH = 0xD9000
RAM (rwx) : ORIGIN = 0x20004650, LENGTH = 0x38000
}

Any Ideas?

RE: Soft device 7.2.0 Flash and RAM configuration

DaveC — Thu, 01 Apr 2021 10:41:38 GMT

Update, Sorry I just realized my Linker script was incorrect, should have been

MEMORY
{
FLASH (rx) : ORIGIN = 0x27000, LENGTH = 0xD9000
RAM (rwx) : ORIGIN = 0x20004650, LENGTH = 0x38000
}