esp_now_one_to_many_example.ino

#include <esp_now.h>
#include <WiFi.h>

// REPLACE WITH YOUR ESP RECEIVER’S MAC ADDRESS
uint8_t broadcastAddress1[] = {0xE8, 0x31, 0xCD, 0xD6, 0xE9, 0x20};
uint8_t broadcastAddress2[] = {0xEC, 0x62, 0x60, 0x84, 0x31, 0x78};
uint8_t broadcastAddress3[] = {0xEC, 0x62, 0x60, 0x84, 0x31, 0x04};

typedef struct message_struct {
  bool Start_show = true;
  bool Stop_show = false;
 
} message_struct;

message_struct Start_show1;
message_struct Start_show2;
message_struct Start_show3;

esp_now_peer_info_t peerInfo;

void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
  char macStr[18];
  Serial.print("Packet to: ");
  // Copies the sender mac address to a string
  snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",
           mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
  Serial.print(macStr);
  Serial.print(" send status:\t");
  Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Delivery Success" : "Delivery Fail");
}
 
void setup() {
 
  Serial.begin(115200);
 
  WiFi.mode(WIFI_STA);
 
  if (esp_now_init() != ESP_OK) {
    Serial.println("Error initializing ESP-NOW");
    return;
  }

  esp_now_register_send_cb(OnDataSent);

  // register peer
  peerInfo.channel = 0;  
  peerInfo.encrypt = false;
   
  memcpy(peerInfo.peer_addr, broadcastAddress1, 6);
  if (esp_now_add_peer(&peerInfo) != ESP_OK){
    Serial.println("Failed to add peer");
    return;
  }
 
  memcpy(peerInfo.peer_addr, broadcastAddress2, 6);
  if (esp_now_add_peer(&peerInfo) != ESP_OK){
    Serial.println("Failed to add peer");
    return;
  }
  memcpy(peerInfo.peer_addr, broadcastAddress3, 6);
  if (esp_now_add_peer(&peerInfo) != ESP_OK){
    Serial.println("Failed to add peer");
    return;
  }
}
 
void loop() {

  Start_show1.Start_show = true;
  Start_show1.Stop_show = false;
  Start_show2.Start_show = true;
  Start_show2.Stop_show = false;
  Start_show3.Start_show = true;
  Start_show3.Stop_show = false;
 
  esp_err_t result1 = esp_now_send(
    broadcastAddress1,
    (uint8_t *) &Start_show1,
    sizeof(Start_show1));
   
  if (result1 == ESP_OK) {
    Serial.println("Sent with success");
  }
  else {
    Serial.println("Error sending the data");
  }
  delay(500);
  esp_err_t result2 = esp_now_send(
    broadcastAddress2,
    (uint8_t *) &Start_show2,
    sizeof(message_struct));

  if (result2 == ESP_OK) {
    Serial.println("Sent with success");
  }
  else {
    Serial.println("Error sending the data");
  }
 
  delay(500);  
  esp_err_t result3 = esp_now_send(
    broadcastAddress3,
    (uint8_t *) &Start_show3,
    sizeof(message_struct));
   
  if (result3 == ESP_OK) {
    Serial.println("Sent with success");
  }
  else {
    Serial.println("Error sending the data");
  }
  delay(2000);
}