implementing custom service

[Srikara]

product details:

nRF52840 custom board

nRFConnectSDK 2.2.0

we want to implement custom service interacting with the Android app.

Where we will receive on command from Android app and we will do some processing and sending the data back to the android app.

For this what and all we need to do.

for ex: service

what characteristics and what descriptors are needed and their properties.

All we need to know is how to write custom service and for our requirement what we need to add.

[Sigurd Hellesvik]

Hi,

Here in Norway we have had the Easter holidays, causing the delay in the answer. But we are all back in office now.

To learn how to add new services to a BLE device, I recommend our Bluetooth Low Energy Fundamentals guide.

Regards,
Sigurd Hellesvik

[Srikara]

Hi

Sorry i was completely occupied with multiple objects. Did not get time to look into this.

Got some breathing time. This we are planing initially as POC.

THe requirement is: Custom service where

1.From APP to NRF initially one request comes to send the data

2.As the request comes the data will be sent from NRF to Android App.

3.One main thing is this service and characteristics should run parallelly with the SMP service which as part of other PRIVATE case is handled.

SO DFU and this custom service should work parallelly.

For Both to work, how two services need to be implemented and what should be the custom service characteristics.

[Srikara]

Ok Ok got it. You are saying in the settings we can select to see all the device instead of running with SMP server.

Will test that, may not be now as busy in other project/issues. \

Thank you.

[Sigurd Hellesvik]

Srikara said:

Ok Ok got it. You are saying in the settings we can select to see all the device instead of running with SMP server.

Yes.

And if you make your own phone app later you can make that phone app sort for your UUID specifically

[Srikara]

hi,

Like in  nRF 5 sdk , do we have any sample which supports UART over BLE.

We want to recive the request from the Android app and then send the data to app.

THe data is read from UART in nRF.

One more thing is

1.We will receive request from Android app(actually read RFID data)

2.we will be sending the data to Android app--> this data may be continuous(this will be RFID tags data)

For this i feel two characteristics needed.

. service 

     .--- Read Chracteristic   ----READ

      --- write characteristic    ---- WRITE

Do we need Descriptor and NOTIFY  in WRITE case/ READ case.

can you suggest on this.

[Sigurd Hellesvik]

Srikara said:

Like in  nRF 5 sdk , do we have any sample which supports UART over BLE.

Yes

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/bluetooth/central_uart/README.html

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/bluetooth/peripheral_uart/README.html

Srikara said:

Do we need Descriptor and NOTIFY  in WRITE case/ READ case.

Android -> nRF: WRITE, do not use notify
nRF -> Android: READ, use notify

[Srikara]

Sigurd Hellesvik said:

developer.nordicsemi.com/.../quote]

Thank you. I have used this peripheral UART. built and falshed onto nRF52840DK. 

Foolowed the steps mentioned in testing column.

Did not understand the point 8.

Also i am able to send in the RX characteristic only test and able to see that data in COM port connection(Teraterm)

to send the data from nRF DK to nRF Connect app pont 12 is not working. I am not seeing any thing happening on the android app side. How to verify the notification?

[Srikara]

Srikara said:

Also i am able to send in the RX characteristic only test and able to see that data in COM port connection(Teraterm)

able to send any data but able to see only test data not byte. But in the RTT logs i can see data is received. Also when send ign data from nRF to android app the data sent is failed.

Sorry. One more point, as per the link you shared i have just build the code without any modifications mentioned in the documentaion.

Will that be need for this to work.

[Sigurd Hellesvik]

The code I shared is meant for two different DKs, one for each sample.

You can also use the UART Peripheral sample together with the https://www.nordicsemi.com/Products/Development-tools/nrf-toolbox, which should make it easy to test.

Does this answer your questions?

[Srikara]

Hi 

with NRF tool box it works fine.

Now this peripheral UART we want to port to other application (which we were discussing in private ticket.).

Now my team head want this app to be ported to our app and also the android app to support this.

Can we suggest the steps to be proceeded to create android app to handle this(we may do it from scratch or already we have some app and we want to add this.)

Usually there will be commands sent on RX characteristic and will receive the data from nRF.

[Sigurd Hellesvik]

For the android app, it is mostly up to you.

However, we have the source code for the nRF Toolbox open source: https://github.com/NordicSemiconductor/Android-nRF-Toolbox. You can use this as inspiration.

[Srikara]

ok sure. Will check that.