Wish ESP8266 Mesh

[positrom2]

As I understood (somehow) the espressif Mesh concept, it allows several ESPs to communicate without being connected to WiFi or the internet.
This is what I like to have, for simplicity, if it works. There is an Arduino library for that:
https://github.com/Coopdis/easyMesh
So one ESP could measure data (BMP280) and send them to another one to evaluate and display them on a LCD. Setting up a Raspi for that task is not comfortable (needing e.g. some (bulky) monitor).
If the two or more ESPs could do that job (best from B4R), it would greatly simplify the matter.

 

[Cableguy]

I don't see the need for an extra lib here...
set one ESP as Master (Server Mode) and any number of n ESPs as Slaves and connect to the master ESP.
Use serialization to send/receive data and to identify the sender/receiver.
You can even use any other protocol available, such as mqtt, http, etc

 

[positrom2]

I will see how to get that running.
So the mesh concept was wasting time?
Any of the "other protocol available" seems overshoot if simpler solution is available.

 

[Cableguy]

The simplest would be the serialization method.
Check Erel's exemples about connecting arduino and esp to get you started

 

[Cableguy]

This subject is quite interesting, i may attempt creating à couple of code modules for this... are you up to à joint-venture?

 

[Erel]

I agree with Cableguy. There is no reason to add another layer. It is simple to communicate with other devices or computers. Especially with the new B4RSerializator tool.

 

[positrom2]

@Cableguy:

are you up to à joint-venture?

Why not.
Will keep you informed. Will also compare with the "mesh" approach (arduino).

 

[Erel]

Setting up a Raspi for that task is not comfortable (needing e.g. some (bulky) monitor).

Note that you don't need a monitor to work with RPi. Configure the router to assign a specific ip address to the RPi and from now on you can use SSH (putty) to access it.

 

[positrom2]

Mesh: Really fascinating.

 

[Cableguy]

Its a very cool video, BUT, something is eluding me...
From what I read i the github you shared, the mesh connects in adhoc mode, meaning that there is no Master/Slave relation, however, to the best of my knowledge, adhoc is only possible between no more than 2 devices (?)... (after googling, I see I am wrong.. need to look deeper into this)

Plus, the addition of a webapp, in my way of viewing things, makes the smartphone a Master device, which controls any other "smart block" that get's added to the network... the fact that the "smart blocks" react to another block being added or removed may be explained by the webapp behaviour too...

I will first gather a few ideas and notions, and figure out what would be the better approach to a similar behavior, but without the webapp...
What I can see as a "real world" use, is a esp based "smart display" (like the nextion) which will react to other "nodes"(sensors) being added to the mesh and show their info... I have 2 ESP to try out, plus a few smartphones that can simulate other nodes.. will see how that Goes, maybe i'll get a few more ESPs

 

[Erel]

This is a very good use case for MQTT. The broker can run on the Android device, a PC or a SoC such as Raspberry Pi.

MQTT is really a great solution for communication between multiple devices.

 

[Cableguy]

This is a very good use case for MQTT. The broker can run on the Android device, a PC or a SoC such as Raspberry Pi.

MQTT is really a great solution for communication between multiple devices.

Yes, but it still is an "outside service", which in more simpler cases (you may also read as "private restricted") is something you want to avoid all together

 

[Cableguy]

@Erel, have you tried this "setup"?

http://www.esp8266.com/viewtopic.php?p=53628#p53628

If I read correctly, a single ESP functioning both in AP AND server mode (?)

 

[positrom2]

The WebApp shown in the video is not required.
Here I am running two ESPs in a Mesh configuration (Example "Hello Mesh" from the Arduino Mesh lib):
Works the same with three ESPs.

On com8 I get this (Added the Com8 and Com13 strings for better distinguishing).
"Com8: Setting up mesh node...
received: Com13: Hello world response #0 from Mesh_Node10775221.
received: Com13: Hello world response #1 from Mesh_Node10775221.
...."
On com13 I get this:
"Com13: Setting up mesh node...
received: Com8 request #6 from Mesh_Node13927457.
received: Com8 request #8 from Mesh_Node13927457.
..."

 

[Erel]

If I read correctly, a single ESP functioning both in AP AND server mode (?)

This is used in this example: ESP8266 - WiFi Remote Configuration

Check this example: https://www.b4x.com/android/forum/threads/arduino-pc-file-transfer.67682/#content
Multiple clients can communicate with the server as each request is closed after the response is sent.

Still, I would have chosen MQTT as it is more robust.

 

[Cableguy]

from what I was able to gather from several researches, true ad-hoc mode is not possible with the ESP...
however, since at least 2 devices are needed to establish a "pseudo ad-hoc" network, I started creating a code module that will first search for a given network SSID, and if found, connect to it... if not found, then it will establish it self as the master...

 

[Cableguy]

This is used in this example: ESP8266 - WiFi Remote Configuration

Check this example: https://www.b4x.com/android/forum/threads/arduino-pc-file-transfer.67682/#content
.

in that example, the board connects either in AP, or to a given network... my question is, can both modes be used at the same time in a single board?

 

[Erel]

I think that it is not possible. It is also not the "correct" way if you want to implement a reliable solution.

 

[Samuel Ramirez]

In my opinion, MESH for ESP8266 (and any other communication devices) is a very important feature for networks. It will be more used in IoT solutions.
The implementation of the MESH network feature for the ESP8266 was done by Espressif. The importance of wireless MESH networks is based on the fact that these networks are dynamic, self-organizing, adaptive or static, deterministic and all of these benefits are implemented by Espressif in their SDK. I understand that implement a specific mesh library for ESP8266 will require development time but if done, it will be very useful.

 

[gmag11]

A mesh makes sense when the number of devices is relatively high. An ESP8266 configured as AP can accept a maximum of 4 devices, and home wifi routers have a similar (normally higher) limitation.

If you want, for instance, to create a network with many devices, a mesh is the best solution. This concept is used by xBee and ZWave. Using WiFi is probably worse than those technologies because its range is limited to some tenths meters but... ESP8266 is so cheap.

EasyMesh is a good approach that does not limit the maximum number of devices. It uses a concept where all nodes have the same weight, there is no master node.

You can connect another device (like a RaspberryPi) to the mesh easily, without especial hardware but WiFi adapter, and get data from mesh to the cloud. You only need some Python (or any other language) code to make a TCP connection to your connection point.

EasyMesh development has not been developed since some months. That's why we have created a fork called PainlessMesh that may be worth to test. If you'd like to, it is available on https://gitlab.com/BlackEdder/painlessMesh