How do I test example project iot mqtt publish and subscribe projects?

[Olaf]

The example projects I am referring to is located here:

nRF5_SDK_15.2.0\examples\iot\mqtt\lwip\subscriber\pca10056\s140\ses\iot_lwip_mqtt_subscriber_pca10056_s140

nRF5_SDK_15.2.0\examples\iot\mqtt\lwip\publisher\pca10056\s140\ses\iot_lwip_mqtt_publisher_pca10056_s140

Using a window10 pc:

I have build and downloaded pub program to one nRF52840DK and sub to another nRF52840DK successfully. On my smart phone I can see both of them as Bluetooth devices.

As new to Nordics products and IDE it would be nice with guides/documentation as how to verify that this MQTT pub/sub projects works ( as well as all the other example projects ). 

Do I need another Linux board to work as the MQTT broker? Or does the subscriber board also works as a broker?

Appreciate a link to documentation/guides that explain the many example projects.

Thanks

[bjorn-spockeli]

Yes, you need a 3rd device that acts as the MQTT Broker, see Setting up the Mosquitto MQTT broker for information on how to set this up on a Windows, Linux or OS X device. 

The MQTT examples are documented here, Experimental: IoT Examples / MQTT. Each example have a Testing subsection in their documentation, explaining step by step how to test the examples, see 

MQTT Client - Publisher / Testing

MQTT Client - Subscriber / Testing

Best regards
Bjørn

[Olaf]

Thanks for your reply. If I don't have the option of a 3rd device MQTT broker, is there a preferred protocol / best way to send and receive data/commands between two BLE devices? I assume it has to be a master-slave relationship, and payload be structured as a JSON document, and it has to be BLE5 to have a payload size of 253 bytes.

Thanks

[bjorn-spockeli]

You mean just a regular BLE connection ? If that is the case, then you should take a look at the  Experimental: ATT_MTU Throughput Example. 

[Olaf]

Thank you Bjorn for links to example projects and test documentation. 

Learned a lot from ATT_MTU example, returning to MQTT example

I have a question to the "BLE enabled router"

The nRF52840DK doesn't have wifi so it cannot act as the BLE/WIFI router unless I add a wifi module to it! Is that correct? Can I use a Raspberry Pi as BLE/WIFI router?

What HW is best to test MQTT example project? 

Thanks

[bjorn-spockeli]

Yes, that is correct. Yes, I have set up the Raspberry Pi as BLE/ Wifi Router, see Setting up BLE 6LoWPAN Border Router.