Phone to node mcu to node mcu communication

Need Help With My Project
1

Hi, was not able to find something similar or maybe i’m bad at searching, but is there a way to make phone -> node mcu -> node mcu comonication?

What I want is to be able to connect via wifi to one node mcu, send data to it and then from that node mcu board data will be send via wifi to other one that is connected to it.

What I’m really need to know is there a way for node mcu board to be connected to a wifi, but also act as accses point?

2

The communication route is:

Blynk app (on Phone) <—> Blynk Server <—> Device(s) (NodeMCUs)

There is no phone to NodeMCU communication via WiFi, it goes via the Blynk server.
Multiple devices (NodeMCUs) can talk via the server to the same app project, but always via the server when using WiFi.

Maybe if you explained in more detail what you are trying to achieve then we might be able to help with an alternative to the one that you’ve visualised.

Pete.

3

What I want to create is like diy home security system using multiple node mcu and I want to be able to control those (get data and send data) from my phone. And my idea is to have one node mcu lets say as a SERVER and all other ones as a CLIENTS. What I want to do is to connect that SERVER to my home wifi and to be able to connect to it from my phone when phone is connected to same wifi. And idea i have is to send data to that SERVER (some kind of costum commands) and that SERVER would process those commands and data and send it to specific CLIENT.

4

You’d be creating lots of unnecessary work for yourself doing it that way, as you’d need to use a device-to-device communication protocol which you’d then need your ‘server’ NodeMCU to translate into Blynk communications.

Better options are:

  1. run Blynk code on all devices and use Blynk Bridge to handle your device-to-device communication, and have one (or more) of your devices as the master (‘server’) which makes the logic decisions.

  2. go down the Node-Red/MQTT route, so that device to device communication is done via MQTT and have the logic decisions made by Node-Red, as well as providing the link to Blynk.

  3. use a lightweight MQTT service for device to device communications and write your own Blynk/MQTT interface.

Pete.

5

Or use ESP32 Bluetooth communication, W/Wo blynk :thinking:

6

Can you have multiple Bluetooth connections to the Blynk app?

Pete.

7

I never tried :thinking:

8

I don’t think Bluetooth is a viable option, as all devices would need to be within range of the phone with the Blynk app on it. Not really what you need for a home security system.

Pete.

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