client_b.ino

#include <ESP8266WiFi.h>


// credentials for server_a AP
const char* ssid = "phoxlightpublic";
const char* pass = "phoxlightpublic";

// ip and port for server_a tcp server
IPAddress serverIP = {192, 168, 4, 1};
const int port = 6262;


void setup(void){
    Serial.begin(9600);

    // connect to AP
    Serial.print("Connecting to ");
    Serial.println(ssid);

    WiFi.begin(ssid, pass);
    int status = WiFi.status();

    while(status != WL_CONNECTED){
        delay(500);
        status = WiFi.status();
        Serial.print(status);
    }

    IPAddress ip = WiFi.localIP();
    Serial.print("Connected!");
    Serial.print("IP: ");
    Serial.println(ip);
}

void loop(void){

    // wait a sec
    delay(1000);

    // try to connect to server_a
    Serial.print("Attempting to connect to");
    Serial.print(serverIP[0]);
    Serial.print(serverIP[1]);
    Serial.print(serverIP[2]);
    Serial.println(serverIP[3]);
    WiFiClient client;
    int connectState = client.connect(serverIP, port);
    Serial.print("connectState: ");
    Serial.println(connectState);
}

server_a.ino

#include <ESP8266WiFi.h>


// credentials for AP
const char* ssid = "phoxlightpublic";
const char* pass = "phoxlightpublic";

// ip and port for tcp server
IPAddress serverIP = {192, 168, 4, 1};
const int port = 6262;

WiFiServer server(port);


void setup(void){
    Serial.begin(9600);

    // bring up AP
    Serial.println("Setting up AP");
    WiFi.mode(WIFI_AP);
    WiFi.softAP(ssid, pass);
    Serial.println("AP up!");

    IPAddress ip = WiFi.softAPIP();
    Serial.print("AP IP: ");
    Serial.println(ip);

    // bring up tcp server
    Serial.println("Setting up server");
    server.begin();
    Serial.println("Server up!");
}

void loop(void){
    // check for clients
    WiFiClient client = server.available();
    if(!client){
        return;
    }

    // yay! got one!
    Serial.println("Got client!");

    while(!client.available()){
        delay(1);
    }
    client.flush();
}