Viability question

(Probably not the best/right place to ask, but.....)

I'm stuck with which way to go:
I have NR running on my RPI and it is coping with it, but it is headless and is the "brains" to the system.

I need a display system.

The question is which way to go.
Do I get another RPI (I don't want to overload this one) and connect a display (like: display)
Or do I go with an Arduino MEGA?

It has many outputs to drive LEDs (Neo-pixel probably - though with those you only really need one pin) and other things.
It has buckets of memory so it can listen to my MQTT topics and act on them.

I also believe I can attach a display to it too.
Though looking at the link above, $14 with a free RPI 3 is tempting!
(Ok I'll take that back. Read the "terms and conditions". Should have known better.)

I am still not sure about RPI GPIO for things like buttons to acknowledge notifications, etc.
The arduino I/O is a bit "easier" at this stage.

Has anyone done anything like this and has any tips for a new person?

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The Arduino MEGA has no built in Networking so MQTT is going to be difficult unless you add a Network shield.


But WiFi isn't that difficult. Though Cat-5 is/would be sort of preferred.

It isn't an easy choice.

Then you would need a WiFi shield.

Either way, a "network" (of either type) will be needed.

Yes, a RPI (Zero?) has built in WiFi.

But as I said, I am not that up to speed with RPI GPIO. I am familiar with Arduino GPIO.

Just to put in another suggestion...

I, like a number of people on the forum, use ESP8266-based devices - for example the WeMos D1 Mini to sense things and drive LEDs, relays etc (rather than getting the Raspberry Pi to do it).

You can flash the WeMos with ESP Easy firmware and talk to/from your RPi using MQTT.

All the above is very easy to set-up, and there are lots of people who can help on this forum.

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Node red has RPI Gpio nodes that are easier to use than on the Arduino. If you really need an Arduino environment then I would use an ESP8266 or ESP32 - loads of memory, IO's and built in Wifi, also cheap, boards are available with OLED displays too.


I shall have to check the specs on that device.....

I buy all my WeMos devices, for my IoT students, from Ali Express and Banggood in China.
Must have bought over 40 devices over the last 18-months and have had no problems at all.

Here's a link to the ESP Easy firmware-releases page:

Sorry to disagree - but I disagree! While it is true that you can access them from higher level languages, the physical connections are not as robust and the consequences of getting something wrong are much more severe.

Also, separating out the "concerns" is generally a good idea.

The bottom line of this query is how complex you want your "screen" to be. If you need a high level of complexity, using a device like a Pi with a screen attached gives you access to a browser - perhaps running in kiosk mode - so a very rich UI. However, if you just need something a bit simpler, maybe a bit smaller, then an ESP8266 or ESP32 with an attached screen would probably be a better and cheaper approach. For example, I got an M5stack not so long back, that is ESP32 based with a screen and 3 buttons. Not too expensive and well supported by libraries that help build UI's.

If you go the Pi route, expect to pay a lot more because it is unlikely that you will be satisfied with one of the 3" low cost displays - I have one of those and it really isn't that useful in most cases.


If you have an old tablet lying around that makes a pretty good UI for a node-red dashboard system.


For me, remote display is the way to go (either phone, tablet or laptop). However. the issue for me is initially getting the ip address on the NR server to use dashboard, remote access, etc. Of course you can use Fing and similiar apps, that means another step and extra time waiting to scan the network. Also you can fix the ip address, but that means it is limited to one network and extra initial setup. What I am using is a cheap display (i2c oled or the most economical is i2c lcd), which just display the ip on successful power up. With the ip displayed, we can access the NR server or pi easily with whatever method you want, and also know that the pi booted successfully. It works good for me.

Every Pi I have runs headess. From my laptop I ssh into them or use a web interface to access the data.

Adding a monitor to the Pi wont add any substantial overhead to the workloads you are probably generating.

Log in over ssh and type "ip address"

Sorry but I really have to disagree here, especially for earlier Pi's and Pi Zeros. Also if you are wanting to run multiple services, running the desktop makes a massive difference to performance as you start to hit paging issues.


Always someone who feels they need to...

Suppose your idea is run entire window manager desktop environment to get a "display". Run an X window with just the application you want displayed. It is Linux, not windows you know...or maybe you don't.

Nope, I don't need a gui at all - it is Linux you know, not Windows :wink:

SSH and SCP is more than enough for the most part.

If I do need something more, webmin is enough.

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Totally agree with Totallyinformation (too may totals!), ssh and accessing the dashboard is more than enough for most purposes. @ghayne , to SSH or access dash board you still need to know the ip address in the first place, hence my suggestion of using a low cost, low over head display like oled or lcd to display the Pi address at startup. I have used OLED with node-red-oled node and ip nodes and also tried LCD and works good. That way I just look at the OLED and the Pi's ip is shown.

Hi, would you mind telling what hardware you bought (link?) And how you connected it & programmed it? I'm interested in doing something similar but have very little time. Ta.

Here's a good example

But the Pi usually comes with Avahi/Bonjour enabled so you can usually just ping (your hostname).local to find it or indeed just ssh to that. Bonjour is built into Mac. On Linux just sudo apt-get install avahi-utils and on windows just install the Bonjour print service available free from Apple.

Even esp8266/wemos/arduino can join in by using one of the mdns libraries.

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