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Please help me, h743 Ethernet

Posted: Sat Nov 13, 2021 3:56 am
by wangshujun@tom.com
After the firmware of h743 sets MSS greater than 942, sending packets greater than 942 bytes will fail
If MSS is set to be less than 942, the sending process can transmit packets normally
I expect to set the MSS to a maximum of 1460 for normal Ethernet

Re: Please help me, h743 Ethernet

Posted: Tue Nov 16, 2021 1:03 am
by wangshujun@tom.com
More tests are reported in the GitHub problem. Now it can be determined that the problem is not TCP, but the underlying problem
https://github.com/micropython/micropython/issues/7980

Re: Please help me, h743 Ethernet

Posted: Wed Nov 17, 2021 1:16 am
by wangshujun@tom.com
After trying pybv11 + w5500, the LwIP system can correctly send 1460 TCP packets, so the restriction is more likely to exist in the ETH layer
However, the actual test speed of w5500 is very disappointing. The wired network speed is not as fast as that of esp32. The network Ping operation of h743 is 1ms, and the w5500 is close to 100ms on average, which is much larger than that of esp32

Re: Please help me, h743 Ethernet

Posted: Wed Nov 17, 2021 11:36 am
by wangshujun@tom.com
lwipopts.h

#define LWIP_CHECKSUM_CTRL_PER_NETIF 1 -> 0

It can solve the errors of large data packets
However, I believe that the ETH module of H7 can meet the checksum operation of large data packets. The problem should be the initialization setting