BLE Audio headset with peripheral with 2 different connections

[MehdiZ]

Hello,

We're trying to build a demo based on the BLE Audio sample with extra BLE services to transmit sensor data.

I have managed to build and run the BLE Audio sample on our custom hardware (based on nRF5340).

At the moment, a nRF5340 audio DK is used as a gateway to stream audio data to our custom HW.

I would like to extend this by adding a custom BLE service to transmit sensor data and to get the custom HW to connect to 2 centrals as shown in this simple diagram:

PC----USB---->DK Audio-GW ---BLE Audio link -----> Custom HW ------BLE link ------> Phone/App

I saw older posts on the forum that talk about extending the audio sample while using the same BLE connection not a different one

Is this feasible? and if so, what is the best approach?  

Best regards,

Mehdi

[Simonr]

Hi

1900 bytes per second should definitely be possible from a Bluetooth LE perspective. You can use the BLE throughput calculator here to get an estimate of how much data you can expect to get on a BLE connection? I assume you also want to do LE Audio here, so you need to account for how much data that will transmit as well.

Best regards,

Simon

[MehdiZ]

Thank you very much for your help.

I managed to get it working.

I'm now trying to add DFU over BLE to the build but I'm overflowing my flash.

../arm-zephyr-eabi/bin/ld.bfd: region `FLASH' overflowed by 16668 bytes

I'm using the internal flash as we don't have external memory on our custom hardware. 

I've attempted to reduce the size by using the following configurations but I was not successful.

CONFIG_DEBUG=n
CONFIG_ASSERT=n
CONFIG_STACK_USAGE=n
CONFIG_THREAD_MONITOR=n
CONFIG_CONSOLE=n
CONFIG_PRINTK=n
CONFIG_BOOT_BANNER=n
CONFIG_SIZE_OPTIMIZATIONS=y

Do you know other configurations I can disable to reduce the build size?

Best regards,

Mehdi