TCP communication freezes after a while on W7500P

Question

Hi, I established an TCP client-server communication with a WIZwiki-W7500P and PC, but the W7500P freezes after some time. The WIZwiki is the client who connect on the server side (PC - Linux). The server sends 1000 bytes each 200 ms. After transfer about 1 MB transferred the communication and the board freezes. The client WIZwiki-W7500P code: int main() { int phy_link; pc.printf("Wait a second...
"); uint8_t mac_addr[6] = {0x00, 0x08, 0xDC, 0x00, 0x01, 0x02}; EthernetInterface eth; eth.init(mac_addr); //Use DHCP eth.connect(); do{ phy_link = eth.ethernet_link(); pc.printf("..."); wait(2); }while(!phy_link); printf("
"); pc.printf("IP Address is %s
", eth.getIPAddress()); TCPSocketConnection sock; int ret = sock.connect("192.168.3.105", 8080); char buffer[1024]; while (true) { ret = sock.receive(buffer, sizeof(buffer)); pc.printf("Received from server: %d
", ret); } sock.close(); eth.disconnect(); } The server Linux: while(1){ n = write(childfd, buf, 1000); if (n < 0) error("ERROR writing to socket"); usleep(1000*200); } Any idea? Does the W7500P IOP implements congestion control? Environment: mbed Best regards

lawrence · Answer

hello, joaopaulob could you capture the packets through wireshark? in tcp communication, it is easy way to check the packet flow. [url]https://www.wireshark.org/download.html[/url] if you do not know how to use wireshark, please ask any thing. thank you

pherig · Answer

I have faced a similar issue and the error was happening because the MCU socket was closing due to a timeout. Wireshark should help a lot and if the problem is in the W7500P side, then I would suggest you to use a debug snippet like this one: void debug_socketSN(uint8_t sn) { printf("WZTOE_Sn_RX_RSR: %d
",(*(volatile uint32_t *)WZTOE_Sn_RX_RSR(sn))); printf("WZTOE_Sn_RXBUF_SIZE: %d
",(*(volatile uint32_t *)WZTOE_Sn_RXBUF_SIZE(sn))); printf("WZTOE_Sn_RX_RD: %d
",(*(volatile uint32_t *)WZTOE_Sn_RX_RD(sn))); printf("WZTOE_Sn_RX_WR: %d
",(*(volatile uint32_t *)WZTOE_Sn_RX_WR(sn))); printf("WZTOE_Sn_SR: 0x%x
",(*(volatile uint32_t *)WZTOE_Sn_SR(sn))); } hope this helps.

lawrence · Answer

Thank you, pherig It is right. These codes are helpful to know the tcp data flow.