[lwip-users] LPC1768 low_level_input dropping packets.

[Hugh Jeremy]

Hi All,

 

I saw a previous post about packets being dropped on this chip which attributed it to the descriptors and buffers not being stored in the AHB RAM. I have that setup on my system but am still dropping packets.

 

I have a system which is running bare metal, I’m currently sending UDP packets at 1ms intervals to be received by the board. Using Wireshark I can see these are being sent at the correct rate. My application code is forwarding the UDP packets to CAN, and I am able to see that it is dropping packets after 250 (i.e. once every 4ms).

 

I found that increasing my number of Rx descriptors, pbuf_pool_size and memp_num_pbuf all have no affect. My understanding was that as packets come in, they are stored in the buffers, and that the `lpc_enetif_input` (part of the LPCOpen library) processes all of the received packets during its scheduled calls.

 

Does anyone have advice on where to start looking to resolve this issue?

Thanks,

 

HJ

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