Where is the space reserved by #define NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE 1408

[Cake Huang]

Hi Devzone team,

In our SDK, say SDK15.0, there is a head file called "sdk_config.h". It contains a line which looks like below:

// <o> NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE - Attribute Table size in bytes. The size must be a multiple of 4.
#ifndef NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE
#define NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE 1408
#endif

It is obvious that this line allocates some space used by soft device.  And the size of this space is a bit big which is more than 1 kilo bytes.

I just want to make sure whether this space is in RAM or in internal program flash?

[Vidar Berg]

Hi, 

The attribute table is stored in the Softdevice's RAM region (memory layout) and the debug log will ask you to increase the APP_RAM_BASE address if it is set too low for the current configuration, hence allocate more RAM for the softdevice. 

[Cake Huang]

Yes, thank you so much.

But I have another question, from DFU memory layout(DFU Memory Layout), what is the code piece allocating the application data area?

What is this application area used for? I know it is inside the program flash.

Hope to get your explain, thank you.

[Cake Huang]

[Vidar Berg]

It's typically used to store application data such as bonding information. Peer manager (FDS/FSTORAGE) uses this region by default. 

[Cake Huang]

Thank you Vidar. Well understand.