How to acheive fast and reliable communication between NodeMCUs?

Question

I have two NodeMCU which have to send data to a server (also a NodeMCU). I want to acheive speed of atleast 10Hz because the sensor sends it at that rate. I have tried websockets and couldn't get transfer rate of more than 1Hz and the data was being put in the buffer.

Any ideas how could I can acheive speed of 10Hz via WiFi?

Thanks for any help.

Answer 1

WiFiClient object wraps a TCP socket. A normal TCP socket is connected to IP address and port. WiFiServer starts a listening socket on a port. If server on listening socket is contacted by a remote client socket, it creates a local socket connected with the remote client socket on a free port and returns a WiFiClient object wrapping the socket. Everything you write or print to a WiFiClient is send to that one remote socket.

If one of your client boards creates a WiFiClient and connects it to IP address and port of the WiFiServer on your 'server' board, then you get there a WiFiClient from server.available() and this two WiFiClient objects are connected. What you write/print on one side you read from the WiFiClient object on the other side.

client socket

if (client.connect(serverIP, PORT)) {
  client.print("request\n");
  String response = client.readStringUntil('\n');
  Serial.println(response);
  client.stop();
}

server side

WiFiClient client = server.available();
if (client && client.connected()) {
  String request = client.readStringUntil('\n');
  Serial.println(request);
  client.print("response\n");
  client.stop();
}