BLE usage on Thingy:91 with HCI_UART

[Gmaciek]

Hi,

I am trying to develop an application for Thingy:91, which would allow me getting data from BLE and sending it to the cloud with LTE. I am working on NCS 1.3.0.

Of course the 'default' way to do it would be just to use lte_ble_gateway sample, but as you know it is not ported to the NCS 1.3.0. This issue has been noted  in this topic, where 8 months ago there was released a patch by Sigurd to the NCS 1.1.0, but there was no updates for newer NCS since that time.

I tried to manually patch all necessary files, according to .diff files included by Sigurd, but I run into compilation errors I couldn't resolve. The problem was that in the file board.c that has been added in this patch in there are two defines DT_GPIO_P0_DEV_NAME and DT_GPIO_P1_DEV_NAME, which are not declared and apparently not used in the 1.3.0 or maybe used with other names:

p0 = device_get_binding(DT_GPIO_P0_DEV_NAME);
+	if (!p0) {
+		LOG_ERR("GPIO device " DT_GPIO_P0_DEV_NAME "not found!");
+		return -EIO;
+	}
+
+	p1 = device_get_binding(DT_GPIO_P1_DEV_NAME);
+	if (!p1) {
+		LOG_ERR("GPIO device " DT_GPIO_P1_DEV_NAME " not found!");
+		return -EIO;
+	}

I am attaching the patch package posted by Sigurd in that topic:

lte_ble_gateway_thingy91.zip

I am going to use another cloud for my usage, so the lte_ble_gateway sample is not the one I need to use, but I believe it is the closest to what I want and it's a good starting point for developing application sending data gathered from BLE.

My main question would be:

- how can I actually access data gathered on nRF52 chip on Thingy:91 to send it with LTE? Is there any solution that works on NCS 1.3.0?

If the only way is porting the HCI_UART and developing application on lte_ble_gateway sample,

- are you planning to release any official patches so that HCI_UART works on Thingy:91?

if no,

- would you have any tips as to how manually port HCI_UART sample to NCS 1.3.0?

I will be grateful for any help.

Maciek

[Gmaciek]

Hey Oyvind,

Thanks for information. I've been working with Connectivity Bridge now, trying to combine it with Zephyr's central_hr sample which worked well on the nRF52DK. central_hr is scanning for heart rate sensors in the area and getting their readings.

I've managed to transfer data over UART_0 between nRF91 and nRF52 on Thingy, so I guess all that's left is to get the data I need on nRF52.

Is that a bad approach? Or will that be somehow cumbersome to migrate zephyr's central_hr to connectivity bridge?

Also, why in this case would I use the peripheral app on Thingy? Thingy should connect directly to heart rate sensor, so if I'm not mistaken it will act as central and the sensor would be peripherals.

Regards,

Maciek

[Øyvind]

Hey Maciek, 

Gmaciek said:

Thanks for information. I've been working with Connectivity Bridge now, trying to combine it with Zephyr's central_hr sample which worked well on the nRF52DK. central_hr is scanning for heart rate sensors in the area and getting their readings.

 Good work, happy to hear you got it running, and that you have got transfer up and running between the devices on the Thingy:91.

Gmaciek said:

Is that a bad approach? Or will that be somehow cumbersome to migrate zephyr's central_hr to connectivity bridge?

 No, this looks like a good solution according to the developer of the Connectivity Bridge.

This line from ble_handler.c forwards BLE data to UART. This event has a pointer that points to a data buffer. This data buffer is freed with this line of code. This is done after other modules have processed the event and had the possibility to copy the data. The ble_data_event is registered as the "FINAL" handler of this event, and therefore allows the former freeing of data. 
For your project, you will then need to generate a ble_data_event from your HRS.

Gmaciek said:

Also, why in this case would I use the peripheral app on Thingy? Thingy should connect directly to heart rate sensor, so if I'm not mistaken it will act as central and the sensor would be peripherals.

You are correct, you would not. That was a quick test that another developer did for proof of concept. 

Let me know how solution above works for you!

Kind regards, 
Øyvind