#include <ESP8266WiFi.h>
 

IPAddress local_IP(192,168,4,22);
IPAddress gateway(192,168,4,9);
IPAddress subnet(255,255,255,0);
const char *ssid = "ESP_AP";
const char *password = "test123";

void setup()

{

Serial.begin(115200);
Serial.println();
Serial.print("Setting soft-AP configuration ... ");
Serial.println(WiFi.softAPConfig(local_IP, gateway, subnet) ? "Ready" : "Failed!");
Serial.print("Setting soft-AP ... ");
Serial.println(WiFi.softAP(ssid, password) ? "Ready" : "Failed!");
Serial.print("Soft-AP IP address = ");
Serial.println(WiFi.softAPIP());

}

void loop() {}

Kaynak : https://arduino-esp8266.readthedocs.io/en/latest/esp8266wifi/soft-access-point-class.html