Issue after modifying linker script to use larger RAM region on STM32N6570-DK

[saib]

Hello ST Community,

I'm working on an STM32N6570-DK project where I've merged two example codes from the STM32CubeN6 repository:

1 . DCMIPP_ContinuousMode

https://github.com/STMicroelectronics/STM32CubeN6/tree/main/Projects/STM32N6570-DK/Applications/DCMIPP/DCMIPP_ContinuousMode 

•   Used for capturing data from the IMX335 camera and displaying it on LTDC.

2 . Nx_WebServer

https://github.com/STMicroelectronics/STM32CubeN6/tree/main/Projects/STM32N6570-DK/Applications/NetXDuo/Nx_WebServer

• Modified to set a static IP and transmit packets over Ethernet and not using the SD card part and FileX.

The merged code compiles successfully in STM32CubeIDE. I've attached a ZIP file containing the full merged project for reference.

Initially, I used the linker script (STM32N6XX_AXISRAM2_fsbl.ld) , which allocates 512KB of RAM (255K + 256K) and manages Ethernet buffers, I attached .txt file named WORKING.

• Camera image is visible on the LCD.

• Ethernet packets (with static data) are sent at ~900 Mbps.

Problem:

I need more RAM for my application. So, I modified the .ld file  , i attached the txt file named NOT_WORKING 

The code still compiles successfully. However, after flashing the via STM32CubeIDE:

• The program flashes correctly but starts executing automatically (without manual reset or intervention).
• No image is displayed on the LCD (camera data not appearing).
• No Ethernet packets are transmitted or received.
• The board does not respond to pings, and networking seems completely non-functional.

The main problem is that , whenever i tried to modify to increase the RAM  size the program starts automatically and struck in Reset Handle.

Questions :

• Why does the program start executing automatically after flashing? In the original setup, it doesn't auto-run like this?

• Are there specific adjustments needed for Ethernet buffers (like .tcp_sec or .nx_data) when scaling up RAM? I removed the absolute addresses, but perhaps they need remapping.

Any help or insights would be greatly appreciated!

Thanks in advance,