由于老是记不住espnow的流程，写一篇博客记一下：
espnow_init
这个函数主要是对各个函数进行一个调用，其实没什么好说的（原来是main函数）
example_wifi_init
对wifi的一个初始化，进行默认的初始化
example_espnow_init
这个是重头戏
在此处用队列形式传递数据，所以要初始化队列
此处则是对espnow的初始化以及对发送和接收函数回调函数进行一个注册
在这块可以看到发送和接收完后会有什么操作
这个就是添加密钥什么的，就是解码加密的东西
接下来就是通过添加要发送的列表添加信息
然后就开始准备发送的数据的数据头
最后通过添加数据的准备和创建任务，基本完成
example_espnow_task
这个也是比较重要的一环，但其实也没什么好说的了，懂了之前的准备函数这个就是为发送完后的回调做准备的，下面是我注释过的函数：
static void example_espnow_task(void *pvParameter)
{
example_espnow_event_t evt;
uint8_t dat[15]; // 第一位为0的时候发送的时候结束进程
uint8_t recv_state = 0; // 判断接收数据的广播还是单独的,判断接收到的是第几个
uint16_t recv_seq = 0; //收到的个数
int recv_magic = 0; // 判断接收数据的优先级
bool is_broadcast = false;
bool is_link = false;
int ret;
vTaskDelay(1000 / portTICK_PERIOD_MS);
ESP_LOGI(TAG, "Start sending broadcast data");
/* Start sending broadcast ESPNOW data. */
example_espnow_send_param_t *send_param = (example_espnow_send_param_t *)pvParameter;
if (esp_now_send(send_param->dest_mac, send_param->buffer, send_param->len) != ESP_OK) {
ESP_LOGE(TAG, "Send error");
example_espnow_deinit(send_param);
vTaskDelete(NULL);
}
while (xQueueReceive(s_example_espnow_queue, &evt, portMAX_DELAY) == pdTRUE) {
switch (evt.id) {
{
case EXAMPLE_ESPNOW_SEND_ED:
{
if(is_link == true&&flag_connet==true)
{
memcpy(dat, evt.payload, 15); // 传入数据
memcpy(send_param->dest_mac,example_macs,ESP_NOW_ETH_ALEN);
example_espnow_data_prepare(send_param, evt.payload); // 传入数据
// ESP_LOGI(TAG, "send data to " MACSTR "", MAC2STR(send_param->dest_mac));
// ESP_LOGI("SEND","%x,len%d",esp_now_send(send_param->dest_mac, send_param->buffer, send_param->len),send_param->len);
flag_sendding=true;
if (esp_now_send(send_param->dest_mac, send_param->buffer, send_param->len) != ESP_OK)
{
ESP_LOGE(TAG, "Send error1");
example_espnow_deinit(send_param);
vTaskDelete(NULL);
}
}
break;
}
case EXAMPLE_ESPNOW_SEND_CB:
{
flag_sendding=false;
if (is_link == false)
{
example_espnow_event_send_cb_t *send_cb = &evt.info.send_cb;
is_broadcast = IS_BROADCAST_ADDR(send_cb->mac_addr); // 比较广播地址，要是不一样则为斯波
//ESP_LOGD(TAG, "Send data to "MACSTR", status1: %d", MAC2STR(send_cb->mac_addr), send_cb->status);
if (is_broadcast) {
send_param->count--;
if (send_param->count == 0) {
ESP_LOGI(TAG, "Send done");
example_espnow_deinit(send_param);
send_xbox_move(0x50,0x00,2000);//震动2秒
vTaskDelete(NULL);
}
}
if (!is_broadcast) {
ESP_LOGI(TAG, "link success");
send_xbox_move(0x50,0x50,2000);//震动2秒
is_link = true;
break;
// example_espnow_deinit(send_param);
// vTaskDelete(NULL);
}
/* Delay a while before sending the next data. 在发送下一个数据之前延迟一段时间。
之前的哪个数据帧里面的延迟时间是在这里用的*/
if (send_param->delay > 0) {
vTaskDelay(send_param->delay/portTICK_PERIOD_MS);
}
ESP_LOGI(TAG, "send data to "MACSTR"", MAC2STR(send_cb->mac_addr));
memcpy(send_param->dest_mac, send_cb->mac_addr, ESP_NOW_ETH_ALEN);
example_espnow_data_prepare(send_param,&recv_seq);
/* Send the next data after the previous data is sent. */
if (esp_now_send(send_param->dest_mac, send_param->buffer, send_param->len) != ESP_OK) {
ESP_LOGE(TAG, "Send error2");
example_espnow_deinit(send_param);
vTaskDelete(NULL);
}
break;
}else{
// ESP_LOGI("espnow", "send success");
break;
}
}
case EXAMPLE_ESPNOW_RECV_CB:
{
example_espnow_event_recv_cb_t *recv_cb = &evt.info.recv_cb;
ret = example_espnow_data_parse(recv_cb->data, recv_cb->data_len, &recv_state, &recv_seq, &recv_magic,dat);
free(recv_cb->data);
//ESP_LOGI("data", "%s", dat); // 此为收到的数据
if (ret == EXAMPLE_ESPNOW_DATA_BROADCAST&&recv_magic==0) {
//ESP_LOGI(TAG, "Receive %dth broadcast data from: "MACSTR", len: %d", recv_seq, MAC2STR(recv_cb->mac_addr), recv_cb->data_len);
/* If MAC address does not exist in peer list, add it to peer list. */
/*如果对等体列表中没有MAC地址，则将MAC地址添加到对等体列表中，必须是未连接状态并且magic为0*/
if (esp_now_is_peer_exist(recv_cb->mac_addr) == false&&flag_connet==false) {
// esp_now_peer_info_t *peer = malloc(sizeof(esp_now_peer_info_t));
// if (peer == NULL) {
// ESP_LOGE(TAG, "Malloc peer information fail");
// example_espnow_deinit(send_param);
// vTaskDelete(NULL);
// }
// memset(peer, 0, sizeof(esp_now_peer_info_t));
// peer->channel = CONFIG_ESPNOW_CHANNEL;
// peer->ifidx = ESPNOW_WIFI_IF;
// peer->encrypt = true;
// memcpy(peer->lmk, CONFIG_ESPNOW_LMK, ESP_NOW_KEY_LEN);
// memcpy(peer->peer_addr, recv_cb->mac_addr, ESP_NOW_ETH_ALEN);
// ESP_ERROR_CHECK( esp_now_add_peer(peer) );
// free(peer);
esp_now_peer_info_t *peer = malloc(sizeof(esp_now_peer_info_t));
if (peer == NULL)
{
ESP_LOGE(TAG, "Malloc peer information fail");
example_espnow_deinit(send_param);
vTaskDelete(NULL);
}
memset(peer, 0, sizeof(esp_now_peer_info_t));
peer->channel = CONFIG_ESPNOW_CHANNEL;
peer->ifidx = ESPNOW_WIFI_IF;
peer->encrypt = true;
memcpy(peer->lmk, CONFIG_ESPNOW_LMK, ESP_NOW_KEY_LEN);
memcpy(peer->peer_addr, recv_cb->mac_addr, ESP_NOW_ETH_ALEN);
ESP_ERROR_CHECK(esp_now_add_peer(peer));
free(peer);
memcpy(example_macs,recv_cb->mac_addr,ESP_NOW_ETH_ALEN);
ESP_LOGI("SAVE","SAVING MAC");
flag_connet=true;//表示已经对接设备了
}
/* Indicates that the device has received broadcast ESPNOW data. */
/*设备收到广播ESPNOW数据。*/
ESP_LOGI("STAT","STATE IS %d",recv_state);
if (send_param->state == 0) {
send_param->state = 1;
}
/* If receive broadcast ESPNOW data which indicates that the other device has received
* broadcast ESPNOW data and the local magic number is bigger than that in the received
* broadcast ESPNOW data, stop sending broadcast ESPNOW data and start sending unicast
* ESPNOW data.
* *如果接收到广播ESPNOW数据，表示另一台设备已经接收到*广播ESPNOW数据，
* 且本地魔术数大于接收到的*广播ESPNOW数据，则停止发送广播ESPNOW数据，开始发送单播数据。
*/
if (recv_state == 1) {//发送回给对面让他确认是否已经存了
/* The device which has the bigger magic number sends ESPNOW data, the other one
* receives ESPNOW data.
*/
if (send_param->unicast == false && send_param->magic >= recv_magic) {
ESP_LOGI(TAG, "Start sending unicast data");
ESP_LOGI(TAG, "send data to "MACSTR"", MAC2STR(recv_cb->mac_addr));
/* Start sending unicast ESPNOW data. */
memcpy(send_param->dest_mac, recv_cb->mac_addr, ESP_NOW_ETH_ALEN);
example_espnow_data_prepare(send_param,&recv_seq);
if (esp_now_send(send_param->dest_mac, send_param->buffer, send_param->len) != ESP_OK) {
ESP_LOGE(TAG, "Send error3");
example_espnow_deinit(send_param);
vTaskDelete(NULL);
}
else {
send_param->broadcast = false;
send_param->unicast = true;
}
}
else if(send_param->unicast == false && send_param->magic <= recv_magic)
{
send_param->broadcast = false;
send_param->unicast = true;
}
}
}
else if (ret == EXAMPLE_ESPNOW_DATA_UNICAST) {
//ESP_LOGI(TAG, "Receive %dth unicast data from: "MACSTR", len: %d", recv_seq, MAC2STR(recv_cb->mac_addr), recv_cb->data_len);
/* If receive unicast ESPNOW data, also stop sending broadcast ESPNOW data. */
send_param->broadcast = false;
}
else {
ESP_LOGE(TAG, "Receive error data from: "MACSTR"", MAC2STR(recv_cb->mac_addr));
}
break;
}
default:
ESP_LOGE(TAG, "Callback type error: %d", evt.id);
break;
}
}
}
}标签：ESP,recv,espnow,param,send,peer,data,流程 From： https://www.cnblogs.com/recodemo/p/17822041.html