wildcard characters are not readable

Zakba.1 · ‎2021-12-15

Hi

I use touch gfx wildcard to show characters and variables in the text area but the characters are shown like the attached photo... I configured the MPU as follows but still does not work.

I would appreciate any help. I will upload the LCD photo and MPU codes.

PS:I use stm32f767ig

SDRAM

Qspi

fonts and texts are in IROM.

void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};
 
  /* Disables the MPU */
  HAL_MPU_Disable();
	
	  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.BaseAddress = 0x60000000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_64MB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
 
  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER1;
  MPU_InitStruct.BaseAddress = 0x90000000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_32MB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
 
	
  /** Initializes and configures the Region and the memory to be protected 
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER2;
  MPU_InitStruct.BaseAddress = 0xC0000000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_32MB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_BUFFERABLE;
	
	 /** Initializes and configures the Region and the memory to be protected 
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER3;
  MPU_InitStruct.BaseAddress = 0x20000000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_512KB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_BUFFERABLE;
	
	
  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
 
}

N. SANTINI · ‎2021-12-16

Hi,

From this screenshot it looks like you have a cache issue.

Where is your frame buffer located ?

If it is in external SDRAM (0xC0000000) then I would suggest to set the region as MPU_ACCESS_SHAREABLE.

This indicates that several masters can access it (here LTDC and DMA2D) and that cache must be disabled to guarantee data coherency.

Best regards,

Nicolas