Hello Folks, its me again. I've discovered another strange behavior with the STM32F429ZG device in conjunction with LwIP 1.4.1 (and FreeRTOS). Everything goes smoothly for some time, several transfers and so on. But from one point on, the CRC calculation for all outgoing packets fails or is not executed entirely. In the attached pcap file, I've transferred the same file (~10 MB) from SD-Card several times. Beginning with packet 452 every outgoing IP Header has a checksum of zero. Eventually every packet gets discarded by PC. Then with packet 463, the PC sends another command. The MCU tries to ACK it, but still no CRC. Conclusion: CRC on receive either works or ist not checked by MCU. After the RST from PC, the MCU falls back in auto discovery state. For that, TCP data port 55557 gets closed and a new accept() socket with the same port is initiated. Now we can see a lot of UDP 55555 and DHCP discovery broadcasts. Each of them with the same problem. After a reset of the device, everything is working smoothly again.
CRC calculation is done by HW (SW calculation in LwIP turned off), therefore I would expect another STM bug. Is there something known? Some ideas how to track down this? PC: 192.168.111.63 MCU: 192.168.111.200 Turn on checksum calculation in Wireshark. (UDP/TCP settings) IP-Header_CRC_not_calculated_one_transfer.pcap <http://lwip.100.n7.nabble.com/file/n23334/IP-Header_CRC_not_calculated_one_transfer.pcap> -- View this message in context: http://lwip.100.n7.nabble.com/CRC-of-each-IP-Header-is-not-calculated-after-some-point-STM32F4-tp23334.html Sent from the lwip-users mailing list archive at Nabble.com. _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users