How to find the perfect hardware

Hello friends.

I am currently running my NR-program to read and control my pump. For this i talk to the pump via MODBUS (nodes) and send data (and recieve) to (from) my MQTT server that is running on a vm.

Right now i am using a Rasi 4. Since Rapys became quiet expensive, i look for alternatives.
What my question is:. What parameters do you guys look for at your NR-progam to fit your hardware? Is it the size of the nodes? I look for the cheapest hardware, but that satisfied at the same time Node red that my program runs smooth

thank you

Unless that is a complex task then I would have thought that would be easily performed pi a Pi Zero.

Switch myself now to an Odroid-c4 with 32Gb emcc module.
Nodered, Grafana, Influx, mosquitto it runs all smooth on this Odriod.
Hardware preformance is comparable to the specs of an pi4. eMMC module is much faster then an SD card so the overall performance is faster.
If you order one don't forget to order also the emcc module to sd-card for programming the eMMC module.

For your use case, although I am not sure of Modbus compatible yet, you should check out this thread
[](https://MCU plugin)

With this you can run node-red on an ESP32

thank you for the tip. from what i see this module has not WLAN. or am i missing something.

Hi @Manuel_o

Looking at your use case, I can only underline the proposal of @jmorris644 ... as it is exactly the use case that triggered the creation of the node-red-mcu-plugin.

I replaced the RasPi with an ESP32 & node-red-mcu ... running a quite complex flow 24/7 without any issues.

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i will look into i and thought the whole weekend about it.

"problem" right now that i have (i am not quiet sure it it is doable) and need LAN and WLAN for my project at the same time. There is a ESP32 out there that has POE. (olimex POE ISO).

The problem (that i solved) with my raspi was, that my pump is connected with LAN and sends the data out via WLAN.

Long story short. I dont now, how and if it is possible to tell the ESP32 to use the LAN to communicate with the pump and have an active WLAN connection to send the data via node-red out to my MQTT server
Thats the only reason i am still stepping back from an ESP32 (yet)

thank you

edit: CHATGPT gave me this answer:

Yes, it is possible to use an ESP32-PoE from Olimex to simultaneously use LAN and WLAN. The ESP32-PoE has both an Ethernet port and Wi-Fi connectivity, which allows it to connect to a LAN network via Ethernet and a WLAN network via Wi-Fi at the same time.

To use the ESP32-PoE in this way, you can set up both the LAN and WLAN connections in your code. For example, you could use the Ethernet library to handle communication with your pump over the LAN connection using MODBUS, and the Wi-Fi library to send data to your MQTT server over the WLAN connection.

the question is if it is possible to run a programm on esp32 to use lan and wlan and use node red.

hmm gets tricky=)

We spent some time recently to help @BartButenaers run node-red-mcu on his WT32-ETH01 board.
As @phoddie indicated, there's the possibility to run both interfaces of such a board; there might be some additional work to do - but the way to go seems to be not too far ... as Peter had it already working.

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Yes you could use a wt32-eth01, as described here.

Just to confirm what @BartButenaers and @ralphwetzel note, the ESP32 running Node-RED MCU Edition is technically capable of doing this. There's just a little bit of setup and configuration work that needs to be done to make that easy to use. I'm happy to do that, if someone (you!?) are going to use it.


This additional work, it that for the MODBUS connectivity?

It is to allow node-red-mcu utilizing both network interfaces (LAN & WLAN) at the same time / in parallel.

EDIT: ... so it's perhaps as well a (partial) "Yes", as it seems to be Modbus via IP.

There are a couple bits. One is a detail -- the setup code for the MCU currently waits for both the Ethernet and Wi-Fi network interfaces to be connected before launching the flow. That's not always the right behavior (for most projects, having one is enough).

The other bit is to get an MCU Modbus node in place. As noted in another reply, there's already some work there as part of the pzem-004t sensor.

One thing that's not clear to me, are you running Modbus over Serial or TCP. Both can work -- and in fact the ECMA-419 APIs we use to implement Serial and TCP communication are interchangeable (except for configuration differences, of course) so both should be possible.

hello there,

after running on a raspberry pi I ported all my nodes to an instance running from my father inlaws old android phone.

you can run it on android via a terminal emulator called Termux or a native application with a one time payment.

I find that native android app is the easiest solution for me here is the app that I use
red-mobile (not afiliated) :vulcan_salute:

We company has a product running native Node-RED, and the price is low to $45.
If you are interest, please visit our website:
where to buy A64 board
where to buy PN6400

2nd and 3rd link are login page, absolutely nothing about product...

As we now only sell in China, the url is belong to Alibaba taobao.
The brief data like this:
PN6400: 4DI 4DO 2AO 4 AI /1x485 /1x232 / ubuntu16.04.7LTS
A64: A53 CPU /1GB DDR /8GB eMMC/ WiFi/ BLE
More information please email to me :

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