Noob questions: MQTT, openhab, Orange Pi, Arduino

[pansen]

Hi all,

so, I am a bit confused and before implementing in the dark I thought I'd ask for some clarification.

My setup:

Orange Pi with

• MySensor dev branch, with service running in the background
• nrf24 connected via SPI (sudo ./bin/mysgw -d shows succesful communication with it)
• Openhab2 installed an running (already controlling my Yamaha receiver)

Arduino with

• nrf24 connected like in the guide on this very site
• running some MySensors demo code for dimming a connected LED (from the platformio site)

My questions

• I only need to install the openHab binding from here to see the Arduino-LED test thingy in openHab?
• What would I need a MQTT gateway for? Because technically it is a serial gateway no? (since SPI is a serial protocol) Or does serial gateway only mean RS232?
• What would be the advantage of a MQTT gateway?
• I have read about an openHab cloud service which allows you the control/checking via Internet. Should I use this cloud service or try to expose the orangePi via DDNS?

Thanks already!
pansen

[LastSamurai]

@pansen said in Noob questions: MQTT, openhab, Orange Pi, Arduino:

My questions

• I only need to install the openHab binding from here to see the Arduino-LED test thingy in openHab?
• What would I need a MQTT gateway for? Because technically it is a serial gateway no? (since SPI is a serial protocol) Or does serial gateway only mean RS232?
• What would be the advantage of a MQTT gateway?
• I have read about an openHab cloud service which allows you the control/checking via Internet. Should I use this cloud service or try to expose the orangePi via DDNS?

Thanks already!
pansen

Hi and welcome, I will try to help although I am not using your setup.

• Yes, I think so. You might have to restart the node/gateway so that it sends another presentation message
• This is a bit of a special case: normally you have some kind of arduino running as a gateway that is then connected via serial to your controller (a pi/pc/mac...) In this case gateway and controller are the pi. Serial gateway only means a serial connection between gateway and controller.
• MQTT does the same as the serial gateway (for mysensors) but it's a more general platform that could be used with lots of others controllers too (there are some topics in this forum about this)
• Depends on you I guess. I would not allow internet access via an external service to my home control system. I would use dyndns + vpn to control your device if you need internet access to them (do you really?)

[pansen]

Thanks @LastSamurai, indeed I only needed to restart the node to see the message.
Turns out directly connecting the nrf24 via SPI acts like an Ethernet gateway listening on all interfaces on port 5003. (This information was new to me).

Regarding MQTT: I tried Openhab, but it did not work out of the box with the Ethernet gateway, so I quickly tried domoticz and the SPI-nrf24 worked straight away. Could I have domoticz and OpenHAB (for my 5.1 receiver) running at the same time and communicating via MQTT?

Regarding internet access: No, I actually do not want to expose any actuators but maybe sensors (HVAC, alarms). But this is low prio.