ESP-NOW using WEMOS D1 mini Pro

Master01.ino

//=================================================================================================//
// MASTER                                                                                          //
// Board : LOLIN (WEMOS) D1 MINI PRO                                                               //
// Upload speed : 92160                                                                            //
// CPU frequency : 80 Mhz                                                                          //
// Flash size : 16MB (FS:14MB OTA:~1019KB                                                          //
// Debug port : Disabled                                                                           //
// Debgu level : None                                                                              //
// IwIP variant : v2 lower memory                                                                  //
// VTables : Flash                                                                                 //
// Exception : Legacy                                                                              //
// Erase flash : Only sketch                                                                       //
// SSL support : All SSL ciphers                                                                   //
// visit http://9w2nfe.blogspot.com/ for more projects                                             //
//-------------------------------------------------------------------------------------------------//

#include <ESP8266WiFi.h>
extern "C" {
#include <espnow.h>
}
 uint8_t mac[] = {0xF4, 0xCF, 0xA2, 0x6D, 0x20, 0x2C}; //AP MAC MASTER'S ADDRESS
 
  #define WIFI_CHANNEL 4
  int prevstate_1 = LOW;
  int prevstate_2 = LOW;

// Data structure, must be the same for the slave

struct __attribute__((packed))DataStruct {
  char text[32];
};
    DataStruct button_1;
    DataStruct button_2;


void setup() {
  pinMode(D1, INPUT);
  pinMode(D2, INPUT);
  pinMode(D0, OUTPUT);
  pinMode(D5, OUTPUT);

  Serial.begin(115200); Serial.println();
  Serial.println("Starting ESP-now Master");
  WiFi.mode(WIFI_STA); // Station mode for esp-now controller
  WiFi.disconnect();
  Serial.printf("This mac: %s, ", WiFi.macAddress().c_str());
  Serial.printf("slave mac: %02x%02x%02x%02x%02x%02x", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
  Serial.printf(", channel: %i\n", WIFI_CHANNEL);
  if (esp_now_init() != 0)
  {
    Serial.println("*** ESP_Now initialization failed");
  }
  esp_now_set_self_role(ESP_NOW_ROLE_CONTROLLER);
  esp_now_add_peer(mac, ESP_NOW_ROLE_SLAVE, WIFI_CHANNEL, NULL, 0);
  strcpy(button_1.text, "Button 01 pressed");
  strcpy(button_2.text, "Button 02 pressed");
  Serial.println("Setup finished");
}



void loop() {
  sendData();
}


void sendData() {

  int currentstate_1 = digitalRead(D1);
  if (prevstate_1 != currentstate_1) {
    if (currentstate_1 == LOW) {
      uint8_t bs[sizeof(button_1)];
      memcpy(bs, &button_1, sizeof(button_1));
      esp_now_send(mac, bs, sizeof(button_1));
      Serial.println(button_1.text);
      digitalWrite(D0, !digitalRead(D0));
    }
  } prevstate_1 = currentstate_1;

  int currentstate_2 = digitalRead(D2);
  if (prevstate_2 != currentstate_2) {
    if (currentstate_2 == LOW) {
      uint8_t bs[sizeof(button_2)];
      memcpy(bs, &button_2, sizeof(button_2));
      esp_now_send(mac, bs, sizeof(button_2));
      Serial.println(button_2.text);
      digitalWrite(D5, !digitalRead(D5));
    }
  } prevstate_2 = currentstate_2;
}

Slave01.ino

//=================================================================================================//
// SLAVE                                                                                          //
// Board : LOLIN (WEMOS) D1 MINI PRO                                                               //
// Upload speed : 92160                                                                            //
// CPU frequency : 80 Mhz                                                                          //
// Flash size : 16MB (FS:14MB OTA:~1019KB                                                          //
// Debug port : Disabled                                                                           //
// Debgu level : None                                                                              //
// IwIP variant : v2 lower memory                                                                  //
// VTables : Flash                                                                                 //
// Exception : Legacy                                                                              //
// Erase flash : Only sketch                                                                       //
// SSL support : All SSL ciphers                                                                   //
// visit http://9w2nfe.blogspot.com/ for more projects                                             //
//-------------------------------------------------------------------------------------------------//

#include <ESP8266WiFi.h>
extern "C" {
#include <espnow.h>
#include <user_interface.h>
}
  uint8_t mac[] = {0xF4, 0xCF, 0xA2, 0x6D, 0x20, 0x2C}; //AP MAC MASTER'S ADDRESS


  int Led1 = D1;
  int Led2 = D2;

void initVariant() {
  WiFi.mode(WIFI_AP);
  wifi_set_macaddr(SOFTAP_IF, &mac[0]);
}


#define WIFI_CHANNEL 4

// Must match the controller struct
struct __attribute__((packed))DataStruct {
  char text[32];
unsigned int time;};

DataStruct receivedData;

void setup() {
  Serial.begin(115200); Serial.println();
  Serial.println("Starting Esp-now Slave");
  Serial.print("This node AP mac: "); Serial.println(WiFi.softAPmacAddress());
  Serial.print("This node STA mac: "); Serial.println(WiFi.macAddress());
  pinMode(Led1, OUTPUT);
  pinMode(Led2, OUTPUT);


  if (esp_now_init() != 0){
    Serial.println("*** ESP_Now initialization failed");
    while (true) {};
  }

  esp_now_set_self_role(ESP_NOW_ROLE_SLAVE);
  esp_now_register_recv_cb(receiveCallBackFunction);
  Serial.println("Setup finished - waiting for messages");
}



void loop() {
}

void receiveCallBackFunction(uint8_t *senderMac, uint8_t *incomingData, uint8_t len) {
  memcpy(&receivedData, incomingData, sizeof(receivedData));

  String DataCompare = String(receivedData.text);

  if(DataCompare == "Button 01 pressed"){
  digitalWrite(Led1, !digitalRead(Led1));
  Serial.println(" Message = " + DataCompare);
 }
  if(DataCompare == "Button 02 pressed"){
  digitalWrite(Led2, !digitalRead(Led2));
  Serial.println(" Message = " + DataCompare);
   
  }
}