Can DMA2D be reason for System getting into Hardfault Handler?

Question

Hello ,

We are using Custom board with STM32H7 and professional Embedded Wizard Studio Pro Version 9.00 ( Platform Package Index8 ). Everything works perfectly until when we tested by increasing the speed of touching that subsequently changes the GUI contents rapidly, the system freezes and enter into Hardfault Handler. On reseting, the system works as it is - normal.

Its just that with increasing the speed of touching and subsequently changing the GUI content ( to check robustness ), system enters into Hardfault handler. On changing GUI contents, there is no other operations involved such as passing information through SPI, I2C etc or any interrupts. On debugging the Hardfault, we noticed that problem was due to bus transfer. And we noticed the suggestion here: http://ask.embedded-wizard.de/609/running-on-custom-board?show=622#c622 and changed  EW_USE_DMA2D_GRAPHICS_ACCELERATOR=0  rebuilt the project and tested and its no more entering into Hardfault Handler. Also, we are not using QSPI till now, but we may in future.

So my question is can DMA2D be resposible for freezing AHB Bus and  making system enter into Hardfault Handler? We are using FreeRTOS.

 

 

Answer 1

Hello,

I think the usage of the DMA2D is not causing the problem directly - maybe the changed timing or the changed memory bandwidth is showing the problem.

In order to find the reason for the hardfault, here some ideas to check:

1.) Have you checked your SDRAM to get 100% reliable data? You can use the SDRAM memory test.

2.) Can you please ensure / doublecheck that the GUI application is NOT entered by any other threads/tasks except the GUI thread/task?

3.) Have you checked / adapted your MPU settings according ST application note AN4861? Wrong MPU settings may cause a read access outside the memory areas of your hardware.

4.) Can you try to switch off the compiler optimization? Does this change the effect? Btw: What compiler are you using?

Best regards,

Manfred