LwIP + FreeRTOS™ UDP echo server works on Dev Board, but not on custom board.

[kavyamm]

Split from the Implementing a LwIP and FreeRTOS™ v1 UDP echo server on the STM32F7 series Tutorial;

Moved to the forum for better visibility & discussion.

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@mƎALLEm 

Hi Sir,

I am using the same code that works correctly on the development board. However, when I run the same firmware on the custom board, I am encountering an error.

1. Is there any issue in the schematic related to Ethernet?
2. Can I use the same libraries that are used in the Nucleo-H755ZI-Q board for this LAN?
3. If I use the same library and it gets stuck at netif_add() what could be the issue?

[Wood.Andy · Accepted solution]

LAN8742 pin 2 requires a 10k pull down to 0v.

Look at your working development board schematic.

Andy.

[kavyamm]

@Wood.Andy 
Is it necessary? Can it cause any issue?

[Wood.Andy]

Yes - from the chip manual - 

nINTSEL: nINT/REFCLKO Configuration
The nINTSEL configuration strap is used to select between one of two available modes: REF_CLK In
Mode (nINT) and REF_CLK Out Mode. The configured mode determines the function of the
nINT/REFCLKO pin. The nINTSEL configuration strap is latched at POR and on the rising edge of the
nRST. By default, nINTSEL is configured for nINT mode via the internal pull-up resistor.

You will not be getting any REF_CLK to the CPU.

They don't put spare resistors on boards ;)

Andy.

[Hamady]

Hi @kavyamm 

I had exactly the same issue issue on my board letting INTSEL floating , i was thinking it was related to LED - 

But you need to put it at GND to give clock to MCU.

[kavyamm]

Hi @Hamady @Wood.Andy 

Thank you for the help