Integrating BLE service into an RTOS application

[morpho]

I have an RTOS application into which I integrated a custom BLE service code. Question is, there isn't any need for a separate thread for handling BLE stuff? I see BLE events still fire off fine though not sure how that affects the thread execution.

Also, these BLE events happen within an interrupt?

[run_ar]

Hi,

We have two ways of retrieving events from the SD, Interrupt-driven Event Retrieval and Thread Mode Event Retrieval. We have the SoftDevice Handler library to handle this, but which is used depends on you configuration. Note that we have an example in the SDK that could be helpfull: Heart Rate Application with FreeRTOS

Also note some background information on the Softdevice: Interrupt model and processor availability and System on Chip resource requirements

[morpho]

Thanks. Where's the configuration to switch between interrupt driven and thread mode located?

Also, is sd_ble_gatts_hvx used to set the attribute of the said characteristic? Once done, the new value shall be reflected in the nRF Connect app? I see it's invoked in ble_hrs_heart_rate_measurement_send() which is called when the timer expires

[run_ar]

To change between the models you need to choose a different NRF_SDH_DISPATCH_MODEL

sd_ble_gatts_hvx is used to update the attribute value and send a notification/indication to the peer device.For the notification to be sent to the peer the peer will first have to enable notifications by writing to the CCCD of the characteristic.

[morpho]

i understand the part about updating the attribute value but not quite about the notification. How does it appear in the nRF Connect app?

[run_ar]

In the nRF connect app you will see the attribute value beeing updated. You could try one of the SDk examples. i.e. heart rate service, then eneble notifications for this to see how the value is updated in the nRF connect app. The value will simply be sent to the peer in the first possible connection event. Then you should see it update in nRF connect app.