--- title: "could not able to open socket" url: "https://maker.wiznet.io/forum/13625" markdown_url: "https://maker.wiznet.io/forum/13625/md" type: "Forum topic" category: "Ethernet Chips" author: "Yogesh" created: "2020-01-02T10:23:49+09:00" last_activity: "2020-01-22T01:19:50+09:00" language: "en" views: 2185 replies: 5 source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)" --- # could not able to open socket ## Question Asked by Yogesh on 2020-01-02 in Ethernet Chips. Hi, I am using stm32f105vct MCU and w5500 to establish ethernet communication using UDP protocol. I am able to communicate b/w MCU and W5500 ic using SPI but when i tried to initialise socket for udp protocol , socket is always closed.I tried with all the sockets 0 to 8 but same problem. I am getting PHYCFGR register value as 0xBB. I have pasted my program below. Please help me to fine out the probelm . Program: uint8_t gate_way={0,0,0,0},sub_net={255,255,255,0},my_ip={192,168,0,6},dest_ip={192,168,0,2}; uint8_t udp_packets={10,20,30,40,50,60,70,80,90,100},read_data=0; uint16_t prt=5000,dprt=5000; int main(void) { /* Reset of all peripherals, Initializes the Flash interface and the Systick. */ HAL_Init(); /* Configure the system clock */ SystemClock_Config(); /* Initialize all configured peripherals */ MX_GPIO_Init(); MX_SPI2_Init(); MX_UART4_Init(); //***UDP PROTOCOL// //Initialization setSn_CR(0, Sn_CR_CLOSE); setSn_CR(1, Sn_CR_CLOSE); setSn_CR(2, Sn_CR_CLOSE); setSn_CR(3, Sn_CR_CLOSE); setSn_CR(4, Sn_CR_CLOSE); setSn_CR(5, Sn_CR_CLOSE); setSn_CR(6, Sn_CR_CLOSE); setSn_CR(7, Sn_CR_CLOSE); setGAR(gate_way); setSUBR(sub_net); setSIPR(my_ip); setMR(MR_RST); HAL_Delay(1000); START: // OPEN Socket4 Mode UDP MYPORT 5000 setMR(Sn_MR_UDP); setSn_PORT(4, prt); setSn_CR(4, Sn_CR_OPEN); read_data= getSn_SR(4); if(read_data !=SOCK_UDP) { setSn_CR(4, Sn_CR_CLOSE); goto START; } //SET DESTIP 192.168.0.2 DESTPORT 7760 setSn_DIPR(4, dest_ip); setSn_DPORT(4, dprt); while (1) { wiz_send_data(4,udp_packets,sizeof(udp_packets)); setSn_CR(4, Sn_CR_SEND); HAL_Delay(1000); } } Thanks in Advance ## Replies ### Reply 1 by Mxyxixptlick, 2020-01-02 ![](https://avatars.discourse-cdn.com/v4/letter/y/49beb7/48.png) Yogesh: > setMR(MR_RST); Try configuring your IP address, gateway & subnet AFTER resetting the chip rather than before. Sending the reset command (setMR(MR_RST)) resets all registers to default values, undoing your configuration. ### Reply 2 by Yogesh, 2020-01-03 Thank You for your reply, I have corrected my code as per your suggestion but still i am facing the same problem. I would like to inform you that I am using w5500.h and w5500.c from standard IO library prescribed by [wiznet.io](http://wiznet.io),([GitHub - Wiznet/ioLibrary_Driver: ioLibrary_Driver can be used for the application design of WIZnet TCP/IP chips as W5500, W5300, W5200, W5100 W5100S.](https://github.com/Wiznet/ioLibrary_Driver)). ### Reply 3 by Yogesh, 2020-01-20 [@midnightcow](https://maker.wiznet.io/u/midnightcow), Thanks for the response. I have used sendto() func as you said but still it is not working. please find my code below. ``` /* Includes ------------------------------------------------------------------*/ #include "main.h" #include "spi.h" #include "usart.h" #include "gpio.h" #include "wizchip_conf.h" #include "socket.h" #include #define GREETING_MSG "Well done guys! Welcome to the IoT world. Bye!\r\n" SPI_HandleTypeDef hspi2; UART_HandleTypeDef huart2; char msg[60]; uint8_t dest_ip[]={192,168,0,6}; uint16_t dest_port=5000; void SystemClock_Config(void); void cs_sel() { HAL_GPIO_WritePin(GPIOB, GPIO_PIN_12, GPIO_PIN_RESET); //CS LOW } void cs_desel() { HAL_GPIO_WritePin(GPIOB, GPIO_PIN_12, GPIO_PIN_SET); //CS HIGH } uint8_t spi_rb(void) { uint8_t rbuf; HAL_SPI_Receive(&hspi2, &rbuf, 1,1); return rbuf; } void spi_wb(uint8_t b) { HAL_SPI_Transmit(&hspi2, &b, 1, 1); } int main(void) { uint8_t retVal, sockStatus; int16_t rcvLen; uint8_t rcvBuf[20], bufSize[] = {2, 2, 2, 2}; HAL_Init(); SystemClock_Config(); MX_GPIO_Init(); MX_SPI2_Init(); MX_USART2_UART_Init(); reg_wizchip_cs_cbfunc(cs_sel, cs_desel); reg_wizchip_spi_cbfunc(spi_rb, spi_wb); wizchip_init(bufSize, bufSize); wiz_NetInfo netInfo = { .mac = {0x00, 0x08, 0xdc, 0xab, 0xcd, 0xef}, // Mac address .ip = {192, 168, 0, 2}, // IP address .sn = {255, 255, 255, 0}, // Subnet mask .gw = {192, 168, 2, 1}}; // Gateway address wizchip_setnetinfo(&netInfo); wizchip_getnetinfo(&netInfo); reconnect: if((retVal = socket(1, Sn_MR_UDP, 5000, 0)) ==1) { while(1) { if(sockStatus = getSn_SR(1) == SOCK_UDP) { /* Let's send a welcome message and closing socket */ if(retVal = sendto(1, GREETING_MSG, strlen(GREETING_MSG),dest_ip,dest_port) == (int16_t)strlen(GREETING_MSG)) PRINT_STR(SENT_MESSAGE_MSG); else { snprintf(msg, WRONG_RETVAL_MSG, retVal); PRINT_STR(msg); } break; } else { snprintf(msg, WRONG_STATUS_MSG, sockStatus); PRINT_STR(msg); break; } } } else { snprintf(msg, WRONG_RETVAL_MSG, retVal); PRINT_STR(msg); } /* We close the socket and start a connection again */ close(1); goto reconnect; } ``` ### Reply 4 by Yogesh, 2020-01-21 [@midnightcow](https://maker.wiznet.io/u/midnightcow) Thanks for the reply. I am using Nucleo STM32F103RB development board and w5100 Ethernet shield . STMcubeMX & Atollic true studio for coding ,also I am using wireshark tool to monitor the data. Hardware configuration in Nucleo board. 1.Peripheral: SPI2 2.Pins : PB13,PB14,PB15 & PB12 3.Baud_rate: 18MBits/sec. The code which i have got from following link is modified for my board and it is working for TCP, but the same code is modified for UDP it is not working which i already shared with you. Please find the link below. [github.com](https://github.com/cnoviello/stm32-nucleof4/blob/master/stm32-nucleof4-ethshield1/src/main.c) #### [cnoviello/stm32-nucleof4/blob/master/stm32-nucleof4-ethshield1/src/main.c](https://github.com/cnoviello/stm32-nucleof4/blob/master/stm32-nucleof4-ethshield1/src/main.c) ``` /** ****************************************************************************** * @file Templates/Src/main.c * @author MCD Application Team * @version V1.2.0 * @date 26-December-2014 * @brief Main program body ****************************************************************************** * @attention * *

© COPYRIGHT(c) 2014 STMicroelectronics

* * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. Neither the name of STMicroelectronics nor the names of its contributors ``` This file has been truncated. [show original](https://github.com/cnoviello/stm32-nucleof4/blob/master/stm32-nucleof4-ethshield1/src/main.c) ### Reply 5 by Yogesh, 2020-01-21 I have shared data packets captured from wireshark tool, also i changed Gateway IP value but still not working. [![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/9/916752fd3e11bf0e366b6539ca016d408f3af021.png) image1675×795 54.9 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/9/916752fd3e11bf0e366b6539ca016d408f3af021.png) Thank you, --- Source: https://maker.wiznet.io/forum/13625