calculating available memory

[buja]

Hi,

Softdevice - 112

sdk 17.1.0

I am trying to evaluate the memory of the device. I am using nRF52810 and the datasheet says 192KB flash and 24KB of RAM available.

I am a bit confused. 

• From the nRF connect the file memory layout is showing that, memory till 0x22AA3 is occupied by application and Sofdevice, does that mean that the remaining space can be used by application (0x30000 - 0x22AA3 = 53KB) ?

• The above given is the output from the elf file. My understanding is that the 'text' is the code instructions and it is placed in the flash memory and ".data + .bss" in RAM. Also .bss + .data is adding up to 117 KB !!!! I think I am doing it wrong. What is the space left for user application ?

• Could you please explain or provide link which will help me to understand how the above variables are used ?

[SwRa]

Hi,

Kindly take a look at this for a general understanding of the memory layout: https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/lib_bootloader.html?cp=8_5_0_3_5_0_7#lib_bootloader_memory. All the space that are not used by the softdevice and/or bootloader can be utilized by the application and data storage. 

Could you please explain or provide link which will help me to understand how the above variables are used

As you can see from your macros, the ones with PH_ depict the physical size of the flash and Ram of the chip. The FLASH_START is the start address of the firmware/application. FLASHSIZE depicts the flash available for the application. 

As for the explanation about the output from elf file, kindly take a look at this link: https://mcuoneclipse.com/2013/04/14/text-data-and-bss-code-and-data-size-explained/

Regards,

Swathy