how to send temperature values in nrf5840

[Nivetha]

I'm using Nordic nRF5840 and I want to send the micro controller's temperature every 1 second via Bluetooth. Can you tell me how to implement it?

I found an example named Health Thermometer Service Sample Application. Does it apply for nRF5840? I just want to send the chip's temperature using BLE every 1 sec.

Thanks in advance!

[Knut Auvor Grythe]

The Health Thermometer profile requires to be in a connection. If you're just intending to broadcast the temperature without requiring a connection, there is an old example on Nordic's GitHub page. I recently updated my fork of it to work with SDK 12.3.0: github.com/.../nrf5-ble-app-temp

Disclaimer: I'm not entirely sure if it reads temperatures correctly any more. I'm getting 40°C flat when I try with my pca10001, but I don't think it even has a temperature sensor. I've been planning to modify mine to read from an external, more accurate sensor.

[Nivetha]

Yes, indeed it will be in connection. I am trying to read the nrf5840 chips' temperature at the central device.

[Nivetha]

As of now, I used the health thermometer profile and able to check it via the nrF connect app. But in order to transmit the chip's temperature, do I have to modify the health thermometer service or is the functionality inbuilt already?

[endnode]

I believe so. Definitely you should dive into function call stack during sending of these values to see where the actual temperature value is coming from.

[Nivetha]

Thanks. I got it working. Right now, the values are shown as an indication. Is it possible to change it as Notify?

[bjorn-spockeli]

Yes, you simply have to modify the following line in hts_measurement_char_add() in ble_hts.c

char_md.char_props.indicate = 1;

to

char_md.char_props.notify = 1;