Custom Service Structure

[phipi]

I need to create a service on the nRF52832 that can send large amounts of a few different data types to the central device. For instance

• ADC1 sampling (~256 bytes/s)
• ADC2 sampling (~256 bytes/s)
• IMU orientation (32 bytes/s)

And I also need to be able to receive commands from the central. This would be things like:

• Start/ Stop sampling
• Update device name
• Enter Test Mode
• Device shutdown

Should I create 1 service, and a separate characteristic for each data that I need to send? What's the best way to handle the incoming commands?

[endnode]

Depend on what is your major criteria;) Is it speed hence minimal overhead during GATT service discovery right after connection is established or you don't care about that (e.g. because your use case is rather "all the time connected" or "devices will be always bonded and GATT Server stack will be static hence Client will use cache all the time") and you rather prefer having it "nice"? I guess answering this question will give you also immediately answer to your original one;)

[endnode]

Yes, NUS is exactly such multipurpose "tube" example and that's also the reason why it is so popular;) From GATT Server side you have basically 3 options (pull method through Read and push methods Notification and Identification) from which Notify method is the most effective (only simple command no round-trip needed).