W5500 undefined states and behaviour

Question

Hello, I am working on a W5500 TCP server project, based on this Driver, that will allow me to connect and disconnect any number of times. I use the ETH WIZ click board. The W5500 is configured as a TCP sever and it is connected through SPI with an ADSP 21489. The tcp client I use to connect from laptop to server is telnet. The function that handles the tcp communication is given below. It is called in a for ( ; ; ) loop in the main program. void tcp_com(uint8_t tcp_socket, c_buffer_t* g_in_tcp_buffer, c_buffer_t* g_out_tcp_buffer, uint16_t port) { // socket 0 is used // port number is 14321 uint8_t socket_state; printf("
MODE REGISTER = %x", getSn_MR(tcp_socket)); // not working without this line socket_state = getSn_SR(tcp_socket); /* Get the state of the socket*/ switch (socket_state) { //******************************** SOCK_ESTABLISHED ********************************************** case SOCK_ESTABLISHED: //printf("ESTABLISHED STATE
"); if (g_socket_status[tcp_socket] == SOCK_LISTEN) { setSUBR(SubNet1); printf("
Server connection established via SOCKET %d
", tcp_socket); g_socket_status[tcp_socket] = SOCK_ESTABLISHED; } if ((getSn_RX_RSR(tcp_socket) >= 11)) { /* If there is any received data, process it */ receive_pakages(tcp_socket, g_in_tcp_buffer); } if (c_buffer_available_data(g_out_tcp_buffer) > 0) { int ret = transmit_packages_core(tcp_socket, g_out_tcp_buffer); if (ret > 0 && ret < g_send_length) { printf("
Should send %d, send %d", g_send_length, ret); while (ret != g_send_length) { g_resend_length = retransmit_packages_core(tcp_socket); if (g_resend_length > 0) { ret += g_resend_length; } else if (g_resend_length == ERROR_WINDOW_FULL) { printf("
Window Full"); close(tcp_socket); printf("
TCP Socket Closed!!"); } else { break; } } } } break; //******************************** SOCK_CLOSE_WAIT ********************************************** case SOCK_CLOSE_WAIT: printf("
SOCKET %d : CLOSE_WAIT", tcp_socket); disconnect(tcp_socket); break; //*********************************** SOCK_CLOSED ********************************************** case SOCK_CLOSED: printf("
Socket closed!"); close(tcp_socket); if (g_socket_status[tcp_socket] != SOCK_CLOSED) { setup_conn(); } g_socket_status[tcp_socket] = SOCK_CLOSED; if (socket(tcp_socket, Sn_MR_TCP, port, 0x00) == 0) { printf("
%d : Failed to create socket.", tcp_socket); } break; //*********************************** SOCK_INIT ************************************************ case SOCK_INIT: { int result = listen(tcp_socket); if (1 == result) { printf("
Error entering into listen mode!"); } printf("
SOCKET %d : LISTEN", tcp_socket); g_socket_status[tcp_socket] = SOCK_INIT; } break; //*********************************** SOCK_LISTEN *********************************************** case SOCK_LISTEN: { /* socket is in the listening state. */ g_socket_status[tcp_socket] = SOCK_LISTEN; //printf("LISTEN STATE
"); g_count_retry++; if (g_count_retry >= CONN_RETRY_PERIOD) { printf("
One…

Eugeny · Answer

flonas: It is called in a for ( ; ; ) It may happen that there’s some mistake in the code design, and it branches the way it is not innteded to. Perform the following: into each condition of case put some printf which will be logging the branch currently being executed; when communication will fail get the log and analyze how execution flow is being performed to see if there’re some situations causing misbehave.

jim · Answer

Dear flonas I checked TCP Server function in WIZ550SR module. But I couldn’t find any problem. I think there is another cause. Please make sure SPI interface between DSP and W5500. (SPI CLK speed, SPI driver source of DSP etc…) I used WIZ550SR module for testing. wiznet.io WIZ550SR | WIZnet Co., Ltd. Support fast evaluation & test of WIZ550S2E module and two types of base board for RS-232 & RS-422/485 interface http://wizwiki.net/wiki/doku.php?id=products:wiz550sr:start As you know, printf() has nothing to do with the problem. github.com Wiznet/WIZ550SR/blob/master/WIZ550SR_App/src/ioLibrary/Application/loopback/loopback.c #include <stdio.h> #include "loopback.h" #include "socket.h" #include "wizchip_conf.h" #if LOOPBACK_MODE == LOOPBACK_MAIN_NOBLCOK int32_t loopback_tcps(uint8_t sn, uint8_t* buf, uint16_t port) { int32_t ret; uint16_t size = 0, sentsize=0; #ifdef _LOOPBACK_DEBUG_ uint8_t destip[4]; uint16_t destport; #endif switch(getSn_SR(sn)) { case SOCK_ESTABLISHED : This file has been truncated. show original I changed source code to the following. int32_t loopback_tcps(uint8_t sn, uint8_t* buf, uint16_t port) { uint8_t socket_state; printf(“
MODE REGISTER = %x”, getSn_MR(sn)); // Case 1 //printf(“
MODE REGISTER = %x”, getSn_MR(sn)); // Case 2 socket_state = getSn_SR(sn); #ifdef LOOPBACK_DEBUG uint8_t destip[4]; uint16_t destport; #endif //switch(getSn_SR(sn)) switch(socket_state) { case SOCK_ESTABLISHED : Thanks.

flonas · Answer

Eugeny: Perform the following: into each condition of case put some printf which will be logging the branch currently being executed It seems that every printf() I put changes the behaviour of the program, so this method doesn’t help me too much. One thing I noticed is that removing some printfs that are displayed frequently, from the tcp handler function, determines the server to go from LISTEN STATE to CLOSED STATE, then back into LISTEN STATE then into CLOSED STATE and so on. During this time, the server appears to accept connections, but I get disconnected after a very short period. Also, ping has losses (25% usually). Jim: I checked TCP Server function in WIZ550SR module. But I couldn’t find any problem. I think there is another cause. Please make sure SPI interface between DSP and W5500. (SPI CLK speed, SPI driver source of DSP etc…) I used WIZ550SR module for testing. As you know, printf() has nothing to do with the problem. I will check the SPI connection to make sure it is well configured. What I don’t understand is why the server doesn’t accept connections while it is into LISTEN MODE and why it sometimes responds, sometimes doesn’t respond, to ping requests when this problem happens.

flonas · Answer

Eugeny: Please share code of the following functions: disconnect close setup_conn socket listen Here they are: functions.zip (1.8 KB)

jim · Answer

I think SPI inteface is abnormal. First of all, you have to check SPI inteface and then use W5500. Actually, I don’t know ADSP 21489. I guess you must change SPI option or SPICLK until operation is normal. If you want to verify your HW schematic file, please send an email to support@wiznet.io with your file. Thanks.

flonas · Answer

Jim: I think SPI inteface is abnormal. First of all, you have to check SPI inteface and then use W5500. Actually, I don’t know ADSP 21489. I guess you must change SPI option or SPICLK until operation is normal. I configured the SPI to run in Mode 3 at 10 MHz clock and it works fine. I checked the frequency with an oscilloscope. On the other hand, Mode 0 is still not functioning, even at 500 KHz. It seems that in this mode, the MISO signal is identical to the CS (chip select) signal, regardless of what data I try to transfer. I guess it’s some chip fault. After setting and verifying the IP and MAC addresses, I found that W5500 is not always responding to ping. For example, it may respond to 3 ping requensts, but the 4th and 5th time it stops responding. After that, it may start again responding to ping. I checked the PB bit from the Mode register and it is set to zero. UPDATE: It seems that reading the Sn_SR register in an infinite loop causes the ping problem. Thanks !

flonas · Answer

OK, finally I think I found the problem. After connecting an oscilloscope to the breakout pins, I found out that the connection behaves normally and timing errors dissappeared. After disconnecting the oscilloscope, the problems appear again. Most likely, there’s a problem with the breakout board (some pin floating, I don’t know). Thank you all for the help given !