The code was taken from this site: https://randomnerdtutorials.com/esp-now-esp32-arduino-ide/
You need 2 ESP32's (one is the sender, the other one the receiver). Modify the code to have multiple receivers/senders and to get/set the variables from B4R
Output is something like this:
Sender:
Note: Replace the MAC address to the one of the receiver
Receiver:
Output:
You need 2 ESP32's (one is the sender, the other one the receiver). Modify the code to have multiple receivers/senders and to get/set the variables from B4R
Output is something like this:
B4X:
AppStart
7C:9E:BD:E4:15:50
Sent with success
Last Packet Send Status: Delivery SuccessSender:
Note: Replace the MAC address to the one of the receiver
B4X:
#Region Project Attributes
#AutoFlushLogs: True
#CheckArrayBounds: True
#StackBufferSize: 600
#DefineExtra: #include "rCore.h"
#End Region
'Ctrl+Click to open the C code folder: ide://run?File=%WINDIR%\System32\explorer.exe&Args=%PROJECT%\Objects\Src
Sub Process_Globals
Public Serial1 As Serial
End Sub
Private Sub AppStart
Serial1.Initialize(115200)
Log("AppStart")
RunNative("StartESPNow", Null)
End Sub
#if C
#include <esp_now.h>
#include <WiFi.h>
esp_now_peer_info_t peerInfo;
// REPLACE WITH YOUR RECEIVER MAC Address
uint8_t broadcastAddress[] = {0x24, 0x62, 0xAB, 0xFF, 0xCB, 0x30};
//24:62:AB:FF:CB:30
// Structure example to send data
// Must match the receiver structure
typedef struct struct_message {
char a[32];
int b;
float c;
String d;
bool e;
} struct_message;
// Create a struct_message called myData
struct_message myData;
// callback when data is sent
void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
Serial.print("\r\nLast Packet Send Status:\t");
Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Delivery Success" : "Delivery Fail");
}
void StartESPNow(B4R::Object* o) {
WiFi.mode(WIFI_STA);
Serial.println(WiFi.macAddress());
// Init ESP-NOW
if (esp_now_init() != ESP_OK) {
Serial.println("Error initializing ESP-NOW");
return;
}
// Once ESPNow is successfully Init, we will register for Send CB to
// get the status of Trasnmitted packet
esp_now_register_send_cb(OnDataSent);
// Register peer
//esp_now_peer_info_t peerInfo;
memcpy(peerInfo.peer_addr, broadcastAddress, 6);
peerInfo.channel = 0;
peerInfo.encrypt = false;
// Add peer
if (esp_now_add_peer(&peerInfo) != ESP_OK){
Serial.println("Failed to add peer");
return;
}
strcpy(myData.a, "THIS IS A CHAR");
myData.b = random(1,20);
myData.c = 1.2;
myData.d = "Hello";
myData.e = false;
// Send message via ESP-NOW
esp_err_t result = esp_now_send(broadcastAddress, (uint8_t *) &myData, sizeof(myData));
if (result == ESP_OK) {
Serial.println("Sent with success");
}
else {
Serial.println("Error sending the data");
}
}
#End IfReceiver:
Output:
B4X:
AppStart
24:62:AB:FF:CB:30
Bytes received: 56
Char: THIS IS A CHAR
Int: 14
Float: 1.20
String: Hello
Bool: 0
B4X:
#Region Project Attributes
#AutoFlushLogs: True
#CheckArrayBounds: True
#StackBufferSize: 600
#DefineExtra: #include "rCore.h"
#End Region
'Ctrl+Click to open the C code folder: ide://run?File=%WINDIR%\System32\explorer.exe&Args=%PROJECT%\Objects\Src
Sub Process_Globals
Public Serial1 As Serial
End Sub
Private Sub AppStart
Serial1.Initialize(115200)
Log("AppStart")
RunNative("StartESPReceiver", Null)
End Sub
#if C
#include <esp_now.h>
#include <WiFi.h>
esp_now_peer_info_t peerInfo;
// REPLACE WITH YOUR RECEIVER MAC Address
uint8_t broadcastAddress[] = {0x7C, 0x9E, 0xBD, 0xE4, 0x15, 0x50};
// Structure example to receive data
// Must match the sender structure
typedef struct struct_message {
char a[32];
int b;
float c;
String d;
bool e;
} struct_message;
// Create a struct_message called myData
struct_message myData;
// callback function that will be executed when data is received
void OnDataRecv(const uint8_t * mac, const uint8_t *incomingData, int len) {
memcpy(&myData, incomingData, sizeof(myData));
Serial.print("Bytes received: ");
Serial.println(len);
Serial.print("Char: ");
Serial.println(myData.a);
Serial.print("Int: ");
Serial.println(myData.b);
Serial.print("Float: ");
Serial.println(myData.c);
Serial.print("String: ");
Serial.println(myData.d);
Serial.print("Bool: ");
Serial.println(myData.e);
Serial.println();
}
void StartESPReceiver(B4R::Object* o) {
WiFi.mode(WIFI_STA);
Serial.println(WiFi.macAddress());
// Init ESP-NOW
if (esp_now_init() != ESP_OK) {
Serial.println("Error initializing ESP-NOW");
return;
}
// Once ESPNow is successfully Init, we will register for recv CB to
// get recv packer info
esp_now_register_recv_cb(OnDataRecv);
}
#End If