Master and Slave can now send their State

main/main.c

@@ -26,7 +26,7 @@
 #define CONFIG_ESPNOW_PMK "pmk1234567890123"
 #define CONFIG_ESPNOW_SEND_COUNT 100
 #define CONFIG_ESPNOW_SEND_DELAY 1000
-#define CONFIG_ESPNOW_SEND_LEN 10
+#define CONFIG_ESPNOW_SEND_LEN 250
 #define CONFIG_ESPNOW_LMK "lmk1234567890123"
 
 const char *tag = "Exam";
@@ -70,6 +70,8 @@ static void example_espnow_deinit(example_espnow_send_param_t *send_param) {
 void example_espnow_data_prepare(example_espnow_send_param_t *send_param) {
   example_espnow_data_t *buf = (example_espnow_data_t *)send_param->buffer;
 
+  ESP_LOGI(tag, "Example_Data_SIZE: %u, send_param_len: %d\n", sizeof(example_espnow_data_t), send_param->len);
+
   assert(send_param->len >= sizeof(example_espnow_data_t));
 
   buf->type = IS_BROADCAST_ADDR(send_param->dest_mac)
@@ -79,9 +81,11 @@ void example_espnow_data_prepare(example_espnow_send_param_t *send_param) {
   buf->seq_num = s_example_espnow_seq[buf->type]++;
   buf->crc = 0;
   buf->magic = send_param->magic;
+  buf->payload.isMaster = isMaster;
   /* Fill all remaining bytes after the data with random values */
-  esp_fill_random(buf->payload,
+  /* esp_fill_random(buf->payload,
-                  send_param->len - sizeof(example_espnow_data_t));
+                  send_param->len - sizeof(example_espnow_data_t)); */ // wieso sollte ich das mit random daten füllen
+
   buf->crc = esp_crc16_le(UINT16_MAX, (uint8_t const *)buf, send_param->len);
 }
 
@@ -157,6 +161,12 @@ int example_espnow_data_parse(uint8_t *data, uint16_t data_len, uint8_t *state,
   buf->crc = 0;
   crc_cal = esp_crc16_le(UINT16_MAX, (uint8_t const *)buf, data_len);
 
+  if(buf->payload.isMaster) {
+    ESP_LOGE(tag, "Recived Data from Master");
+  } else {
+    ESP_LOGE(tag, "Recived Data from Slave");
+  }
+
   if (crc_cal == crc) {
     return buf->type;
   }
@@ -379,6 +389,7 @@ static esp_err_t example_espnow_init(void) {
 }
 
 void app_main(void) {
+  // Master Slave Detection, default pin is pull up so ground it and check state
   gpio_reset_pin(Master_SlavePin);
   gpio_set_direction(Master_SlavePin, GPIO_MODE_INPUT);
   int checkMaster = gpio_get_level(Master_SlavePin);

main/main.h

@@ -2,9 +2,11 @@
 #define MAIN_H
 
 #define Master_SlavePin 23
+#define MAX_PAYLOAD_SIZE 250
 
 #define ESPNOW_QUEUE_SIZE 6
-#define IS_BROADCAST_ADDR(addr) (memcmp(addr, s_example_broadcast_mac, ESP_NOW_ETH_ALEN) == 0)
+#define IS_BROADCAST_ADDR(addr)                                                \
+  (memcmp(addr, s_example_broadcast_mac, ESP_NOW_ETH_ALEN) == 0)
 
 static bool isMaster;
 
@@ -39,14 +41,23 @@ enum {
   EXAMPLE_ESPNOW_DATA_UNICAST,
   EXAMPLE_ESPNOW_DATA_MAX,
 };
+
+typedef struct {
+  bool isMaster;
+} __attribute__((packed)) payloadData;
+
+static_assert(sizeof(payloadData) <= MAX_PAYLOAD_SIZE, "payloadData struct is too big to be sent in one part, keep it under 250 Bytes!");
+
+
 /* User defined field of ESPNOW data in this example. */
 typedef struct {
   uint8_t type;  // Broadcast or unicast ESPNOW data.
   uint8_t state; // Indicate that if has received broadcast ESPNOW data or not.
   uint16_t seq_num; // Sequence number of ESPNOW data.
   uint16_t crc;     // CRC16 value of ESPNOW data.
-    uint32_t magic;                       //Magic number which is used to determine which device to send unicast ESPNOW data.
+  uint32_t magic;   // Magic number which is used to determine which device to
-    uint8_t payload[0];                   //Real payload of ESPNOW data.
+                  // send unicast ESPNOW data.
+  payloadData payload; // Real payload of ESPNOW data.
 } __attribute__((packed)) example_espnow_data_t;
 
 typedef struct {