[lwip-users] LPC1768 lpc_low_level_input: Packet dropped with errors (0xffffffff)

[Jan Menzel]

Hi All!
        I'm facing the unpleasant problem that most input packets are dropped
by the LPC1768 low level input if my code is run without IDE connected.
The same code started using the IDE works well and I don't see this kind
of errors. The error message is "lpc_low_level_input: Packet dropped
with errors (0xffffffff)" and generated in lpc17xx_40xx_emac.c around
like 256. It seems that the error code is the same as the init value. (I
also shifted the error message printing up a few lines to avoid
resetting the value before printing, with same results.)
        My code is based on the LPCexpresso example with LwIP 1.4.1 and
FreeRTOS (7.x). I upgraded the RTOS to 8.1.2 and stick with
enet_17xx_40xx.c and lpc17xx_40xx_emac.c from the original example. The
code uses four threads, lowlevel rx and tx-cleanup, tcpip and one for
start and control. This fouth thread calls tcpip_init(), netif_add() and
polls the link state. On link detection it calls netif_set_link_up() and
dhcp_add(), both via tcpip_callback_with_block() (the original code
called dhcp_add() directly, but I had the problem that dhcp offers are
not handled if called directly). Once an IP address is assigned, I'm
using netcon to connect to a server.
        Can anyone explain whats going wrong or point me to where to continue
searching? Thank You!

        Jan