STM32F407 Ethernet LwIP + FREERTOS ping break Hard fault

[ATPL]

Dear team,

I am facing an issue where my device disconnects and drops the ping whenever the master device tries to connect with RS-485 Devices. after some "request timeout" error the device goes into a hard fault.

The application runs on  STM32F407VET6 + LAN8742 Ethernet PHY + Free RTOS

3 Task, 2 Message Queue used in this application 

USART is used as interrupt mode - after receiving complete data, data is put into the message Queue

Total 3 tasks running on the same priority -osPriorityNormal

Task1- Handle TCP: put data into the Message Queue

Task2-  data conversion: get data from the Message Queue

Task3- Handle HTTP request 

Master Device/Software: Modscan32, PLC

Slave Devices (RS-485 Devices): Digital inputs, Digital Outputs, Analog Input, Analog Output

Terminating resistor used at the starting of RS-485 Bus.

Please suggest any solution for this problem, your valuable input will be helpful to me.

Hoping to hear from you soon.

Thanks & Regards,

Rahul

[STea]

Hello @ATPL ,

This is lacking contest on the origin of the Hardfault as no code or call stack were provided to identify which part caused the Hardfault.

I recommend you check this article to help you identify what is causing the Hardfault (I would guess most probably stack is not big enough for handling the  RS-485 communication)
Regards
Hichem