写在前面：
本文章旨在总结备份、方便以后查询，由于是个人总结，如有不对，欢迎指正；另外，内容大部分来自网络、书籍、和各类手册，如若侵权请告知，马上删帖致歉。
同样的，跟上一篇 TCP分析一样，本篇是分析 UDP；不哆嗦了，直接贴代码，你们能看懂的，恩，相信自己
/*
* ESPRSSIF MIT License
*
* Copyright (c) 2015 <ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD>
*
* Permission is hereby granted for use on ESPRESSIF SYSTEMS ESP8266 only, in which case,
* it is free of charge, to any person obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the Software is furnished
* to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or
* substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include "esp_common.h"
#include "udp.h"
#include "bsp_udp.h"
LOCAL struct espconn udp_espconn;
LOCAL esp_udp espudp;
/******************************************************************************
* FunctionName : udp_recv_cb
* Description : Processing the received udp packet
* Parameters : arg -- Additional argument to pass to the callback function
* pusrdata -- The received data (or NULL when the connection has been closed!)
* length -- The length of received data
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR udp_recv_cb(void *arg, char *pusrdata, unsigned short length)
{
os_printf(">>>>> recv udp data: %s\n", pusrdata);
user_UDP_Reveive();
}
/******************************************************************************
* FunctionName : udp_send
* Description : udp send data
* Parameters : none
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR udp_send(void)
{
char DeviceBuffer[40] = "I'm ESP8266";
char hwaddr[6];
struct ip_info ipconfig;
const char udp_remote_ip[4] = { 255, 255, 255, 255};
os_memcpy(udp_espconn.proto.udp->remote_ip, udp_remote_ip, 4); // ESP8266 udp remote IP need to be set everytime we call espconn_sent
udp_espconn.proto.udp->remote_port = 1112; // ESP8266 udp remote port need to be set everytime we call espconn_sent
wifi_get_macaddr(STATION_IF, hwaddr);
os_printf("%s" MACSTR "!" , DeviceBuffer, MAC2STR(hwaddr));
espconn_sent(&udp_espconn, DeviceBuffer, os_strlen(DeviceBuffer));
}
/******************************************************************************
* FunctionName : udp_sent_cb
* Description : udp sent successfully
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR udp_sent_cb(void *arg)
{
LOCAL os_timer_t test_timer;
struct espconn *pespconn = arg;
os_printf(">>>>> udp send successfully !!!\n");
user_UDP_Send();
/*
//disarm timer first
os_timer_disarm(&test_timer);
//re-arm timer to check ip
os_timer_setfn(&test_timer, (os_timer_func_t *)udp_send, NULL); // only send next packet after prev packet sent successfully
os_timer_arm(&test_timer, 1000, 0);
*/
}
/******************************************************************************
* FunctionName : tcp_init
* Description : parameter initialize as a udp
* Parameters : port -- local port
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR user_udp_init(uint32 port)
{
uint8 macaddr[6];
/* 定义 IP结构体 */
struct ip_info info;
udp_espconn.proto.udp = (esp_udp *) os_zalloc(sizeof(esp_udp)); // 分配空间
udp_espconn.type = ESPCONN_UDP;
udp_espconn.proto.udp = &espudp;
/* 读取 station IP信息 */
wifi_get_ip_info(STATION_IF,&info);
/* 获取本地 IP地址 */
udp_espconn.proto.udp->local_ip[0] = info.ip.addr;
udp_espconn.proto.udp->local_ip[1] = info.ip.addr>>8;
udp_espconn.proto.udp->local_ip[2] = info.ip.addr>>16;
udp_espconn.proto.udp->local_ip[3] = info.ip.addr>>24;
os_printf("\n\n*******************************\n");
os_printf("UDP Local IP: %d.%d.%d.%d\n", udp_espconn.proto.udp->local_ip[0], \
udp_espconn.proto.udp->local_ip[1], udp_espconn.proto.udp->local_ip[2], \
udp_espconn.proto.udp->local_ip[3]);
/* 端口号 */
udp_espconn.proto.udp->local_port = port;
os_printf("UDP Local Port: %d\n", udp_espconn.proto.udp->local_port);
/* 读取 station MAC */
wifi_get_macaddr(STATION_IF, macaddr);
os_printf("Local MAC: %02x.%02x.%02x.%02x.%02x.%02x\n", macaddr[0], macaddr[1], \
macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
os_printf("*******************************\n");
espconn_regist_recvcb(&udp_espconn, udp_recv_cb); // 接收回调
espconn_regist_sentcb(&udp_espconn, udp_sent_cb); // 发送回调
espconn_create(&udp_espconn); // 建立 UDP连接
os_printf("\n>>>>> udp setup successful\n");
}
可以看到，上面配置的广播式的发送，你也可以设置成对应远程 IP，同时，相应的调试信息也一一输出了
；下面就来简单添加自己的接口，以便管理
/*
* bsp_udp.c
*
* Created on: 2019年9月5日
* Author: liziyuan
*/
#include "esp_common.h"
#include "bsp_udp.h"
/******************************************************************************
* FunctionName : user_UDP_Send
* Description : udp发送回调用户处理
* Parameters : none
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR user_UDP_Send(void)
{
}
/******************************************************************************
* FunctionName : user_UDP_Reveive
* Description : udp接收回调用户处理
* Parameters : none
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR user_UDP_Reveive(void)
{
}
/******************************************************************************
* FunctionName : udp_communication_task
* Description : udp通讯任务
* Parameters : pvParameters
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR udp_communication_task(void *pvParameters)
{
os_printf("\n>>>>> UDP communication is being created.....\n");
while(1)
{
if (wifi_station_get_connect_status() == STATION_GOT_IP) // 等待连接到 AP
{
break;
}
vTaskDelay(300 / portTICK_RATE_MS);
}
user_udp_init(USER_UDP_PORT);
vTaskDelete(NULL);
}
/*------------------------------- END OF FILE -------------------------------*/
最后放上官方提供的 UDP参考代码链接：ESP8266 Sends UDP data
