Project with STM32F439VIT6. After activating Ethernet (DP83848) USB DEVICE CDC (Virtual com port) works not more. Can anybody suggest me where to look?

[DBaya.1]

I make a big project with F439 MCU and there are many things on the board like WiFi, BT, EEPROM, Flash, GPS and so on. The latest thing I made was activating ETH and it works good at least ping runs perfect. But later I found that the USB OTG HS CDC which worked perfectly now doesn't work. Win10 can not recognize the USB divice and Terminal programm can not connect to the port (port is visible some how), firmware freezing. I appreciate any suggestions.

[TDK]

> firmware freezing

Maybe investigate where/why that's happening.

[DBaya.1]

In a FaultAnalyzer:

Bus, memory management or usage fault (FORCED)

Precise data access violation (PRECISERR)

Bus Fault Address Register (BFAR): 0x20032720

I also attached a screenshot from Debug window...

[TDK]

That address isn’t within the RAM limit. Only 192kB of ram. So something is accessing memory outside of there. Quite a bit outside. Is your linker script okay?
Might be an overrun in the heap.

[DBaya.1]

Many thanks TDK. I played around with HEAp and STACK sizes but had no reaction from freezing. Than I have defined which "something" got access beyond the RAM. I forgot to limit wifi data massive which gets the data by IRQ. Result is HardFault.

[Piranha]

Also take a look on this:

https://community.st.com/s/question/0D50X0000BOtfhnSQB/how-to-make-ethernet-and-lwip-working-on-stm32