ESP8266 Community Forum

This is how i would do it:

https://github.com/gmag11/painlessMesh

Then you configure one (or more) ESP units as the WiFi transmitter up to your end point, and the rest as mesh units. You would more than likely need to disconnect from the mesh to connect to a normal IP wireless AP so having more than one transmitter in your mesh would provide some fault tolerance.

You would also need to implement some sort of elementary PubSub mechanism - at least some sort of ack on your final end point that would tell the mesh that a message had been received so the mesh can remove any messages that have reached the end point.

You haven't really mentioned what latency requirements you have - can you store and forward your data as a chunk? What's the time between transmission?

@davydnorris said:-

You would also need to implement some sort of elementary PubSub mechanism

Surely that could be achieved by using MQTT.

MQTT uses a command and command acknowledgement format. MQTT librarys for the ESPs are well established.

I would consider a scenario where the remote nodes report to a MQTT broker running on a Raspberry Pi.

Or am I wrong?

Such a scheme would remove the nightmare of debugging a board with 12 ESPs on!

What i really want to do is,

I have 12 ESP clients with ESP Now
I want to connect it to 12 ESP Now Listeners/Slaves

These ESP listeners are soldered on one PCB, at about 15mm distance from each others.
Problem 1: I came to know that multiple ESP listener modules can't be mounted on one PCB very close to each other,

All 12 clients can send data at same time to to their receiver end.
Problem 2: But receiver end can't receive data transmitted at same time from 12 devices because in that case transmission collusion will happen and non of receiver will be able to receive data.

AcmeUK wrote:@davydnorris said:-

You would also need to implement some sort of elementary PubSub mechanism

Surely that could be achieved by using MQTT.

MQTT uses a command and command acknowledgement format. MQTT librarys for the ESPs are well established.

I would consider a scenario where the remote nodes report to a MQTT broker running on a Raspberry Pi.

Or am I wrong?

Such a scheme would remove the nightmare of debugging a board with 12 ESPs on!

Yes that's what I use all the time, and the mesh library has some examples using MQTT too