I am still somewhat of a beginner to development with nRF51, but it seems to be that the SDK, specifically all the boilerplate code in the app_template example just to initialize the softdevice and so on generates almost 30 KB of code (using SDK v10, S110 and ARM's GCC 4.9.3 distribution with optimizing with -O3). It also consumes almost 2 KB of RAM already, leaving only 6 KB of RAM for the 16 KB RAM variant (xxaa I believe) of the chip.
Why is the boilerplate already so big? Were the older versions much smaller? This looks to me like one can only use the biggest 256 KB flash and 32 KB RAM variant with the current SDK.
Or are my GCC settings or something like that wrong?
Update: I checked the specific app_template code size. So when compiling the app_template in /nRF51_SDK_10.0.0/examples/ble_peripheral/ble_app_template/pca10028/s110/armgcc with gnu make and the makefile supplied by Nordic (i.e. I compile the exact app_template as it comes with the SDK distribution and with ARM GCC 4.9.3 installed on my system) I get the following output about the sizes (Nordic's makefile uses -O3):
text data bss dec hex filename
27120 112 1884 29116 71bc _build/nrf51422_xxac_s110.out
So we can clearly see that the "boilerplate", i.e. what I consider the least amount of setup code even without actually setting up the BLE services, but just calling ble_stack_init() and the other stuff from the app_template, you need 30 KB already.
Even when using -Os instead of -O3 it's still 20 KB, so 10 KB less, but still a lot:
text data bss dec hex filename
17176 112 1876 19164 4adc _build/nrf51422_xxac_s110.out
