Espressif Systems ESP8266EX - Page 22

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3. Sample Codes
printf("ESP8266󰲧UDP󰲧task󰲧>󰲧socket󰲧OK!\n");
3. Bind a local port.
do{
󰲧󰲧󰲧󰲧󰲧ret󰲧=󰲧bind(sock_fd,󰲧(struct󰲧sockaddr󰲧*)&server_addr,󰲧sizeof(server_addr));
󰲧󰲧󰲧󰲧󰲧if󰲧(ret󰲧!=󰲧0)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧UDP󰲧task󰲧>󰲧captdns_task󰲧failed󰲧to󰲧bind󰲧sock!\n");
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧vTaskDelay(1000/portTICK_RATE_MS);
󰲧󰲧󰲧󰲧󰲧󰲧}
󰲧󰲧󰲧󰲧}while(ret󰲧!=󰲧0);
󰲧󰲧󰲧
󰲧󰲧󰲧󰲧printf("ESP8266󰲧UDP󰲧task󰲧>󰲧bind󰲧OK!\n");
4. Receive and transmit the UDP data.
while(1){
󰲧󰲧󰲧󰲧󰲧memset(udp_msg,󰲧0,󰲧UDP_DATA_LEN);
󰲧󰲧󰲧󰲧󰲧memset(&from,󰲧0,󰲧sizeof(from));
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧
󰲧󰲧󰲧󰲧󰲧setsockopt(sock_fd,󰲧SOL_SOCKET,󰲧SO_RCVTIMEO,󰲧(char󰲧*)&nNetTimeout,󰲧sizeof(int));
󰲧󰲧󰲧󰲧󰲧fromlen󰲧=󰲧sizeof(struct󰲧sockaddr_in);
󰲧󰲧󰲧󰲧󰲧ret󰲧=󰲧recvfrom(sock_fd,󰲧(uint8󰲧*)udp_msg,󰲧UDP_DATA_LEN,󰲧0,(struct󰲧sockaddr󰲧*)&from,
(socklen_t󰲧*)&fromlen);
󰲧󰲧󰲧󰲧󰲧if󰲧(ret󰲧>󰲧0)󰲧{
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧printf("ESP8266󰲧UDP󰲧task󰲧>󰲧recv󰲧%d󰲧Bytes󰲧from󰲧%s,󰲧Port󰲧%d\n”,ret,󰲧
inet_ntoa(from.sin_addr),󰲧ntohs(from.sin_port));
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧sendto(sock_fd,(uint8*)udp_msg,󰲧ret,󰲧0,󰲧(struct󰲧sockaddr󰲧*)&from,󰲧fromlen);
󰲧󰲧󰲧󰲧󰲧󰲧󰲧󰲧}
}
if(udp_msg){
󰲧󰲧󰲧󰲧󰲧free(udp_msg);
󰲧󰲧󰲧󰲧󰲧udp_msg󰲧=󰲧NULL;
}
close(sock_fd);
5. Compile the application program, generate firmware and download it into the ESP8266
module.
6. Power off the module, and change it to operation mode; then power on the module and
run the program.
Result:
ip:192.168.1.103,mask:255.255.255.0,gw:192.168.1.1
ESP8266󰲧UDP󰲧task󰲧>󰲧socket󰲧ok!
Espressif
! /!18 37
2017.05