BLE Peripheral connected to multiple Central devices on nrf52840 DK and SDK V16.0.0 (revisited)

Question

Hello. 
 I am running Segger studio 4.5 on Windows 10 and the ble_app_uart example project that works fine with one connected central device (i.e. iPhone with nRF Toolbox running UART). 
 Now I would like to have two such connections. 
 I found this exact question answered here: https://devzone.nordicsemi.com/f/nordic-q-a/58710/ble-peripheral-nus-connected-to-multiple-central-devices-on-nrf52840-s140-and-sdk-v16-0-0/239409#239409 
 And while that thread solved the problem that time, it does not work for me now... 
 I have changed RAM size and location as suggested, and BOTH link counts in sdk.config.h. (Stopping at NRF_LOG_WARNING("Change the RAM start location... etc. and set the following in the project options: RAM_START=0x2000002C RAM_SIZE=0x3FFD4) 
 For some reason I get no output in the "Debug Terminal" window during debugging, even though I set this in config: #define NRF_LOG_ENABLED 1 #define NRF_LOG_DEFAULT_LEVEL 4 
 However, the code crashes during ble_stack_init() in nrf_drv_clock.c::sd_state_evt_handler() when trying to do CRITICAL_REGION_EXIT. 
 I have also run the project that was kindly made available as a zip-file in the thread above, but it crashes at the exact same spot. 
 
 Any ideas what's going on? 
 
 Thanks, 
 Anders.

AndersF · Accepted Answer

I have this config: 
 #define NRF_LOG_ENABLED 1 
 and 
 #define NRF_LOG_BACKEND_RTT_ENABLED 1 
 
 I'm looking in the window called "Debug Terminal" in the image below.

I've also started the RTT viewer, and although it seems to get a connection, there is no output from the various printouts like the ones in main.c: 
 printf("
UART started.
"); NRF_LOG_INFO("Debug logging for UART over RTT started."); 
 I find this very confusing. Where is the printf and NRF_LOG_INFO supposed to end up, and why are both used?? 
 Oh, hang on... if I put a breakpoint before the NRF_LOG_INFO statement and wait a few seconds before continuing execution, the RTT viewer actually prints. So it needs some time to start up then. Problem solved!

I have seen the RAM and FLASH guide. What I did was to take the value from p_app_ram_start, when in fact I should have taken the value from * p_app_ram_start, i.e. the value it's pointing to. Once I realized that, it seems to be working! Yeah! 
 
 Thanks for the speedy help.

BLE Peripheral connected to multiple Central devices on nrf52840 DK and SDK V16.0.0 (revisited)

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