how can i debug code in ram ?

So far I have not tested "RAM-debugging" with STM32 controllers so these 
are just some hints which might be helpful:

- In the Makefile there is a variable RUN_MODE which is set to FLASH_RUN 
in the file in the archiv. Set it to RAM_RUN. The stetting is later used 
to select the linker-script. Look into the output of make all and verify 
that the *_RAM linker-script is used. The content of RUN_MODE is also 
passed as a preprocessor definition so #ifdef RAM_RUN or #ifdef 
FLASH_RUN can be used in the source-code.

- SystemInit_ExtMemCtl() is called in the reset handler, usually 
SystemInit should do. Initialisation of the external memory interface 
can be enabled by a preprocessor define (see system_stm32*.c). Since 
initialization of the external memory interface can be enabled in 
SystemInit() it might be better to call SystemInit in the reset-handler. 
This may not cause a problem but it might be better to use the method 
intended by the STM library-developers until everything starts up as 
expected.

- I did not check every line in the linker-script for RAM but it looks 
o.k.

- Since the .data output-section is already at the correct location it 
is o.k. to wrap the first for-loop (copy data seg initializers...) with 
#ifdef FLASH_RUN/#endif

- MSP is already set in the reset-handler-function so there should be no 
need to add something for this.

- Since the interrupt-vector-table is also in RAM and not at the default 
location the the beginning of the flash-memory area the location has do 
be configured in SCB's VTOR register before any interrupt is enabled. 
See function NVIC_SetVectorTable in misc.c. Call could be done in the 
reset-handler.

- Since the core should start run the code in RAM, the 
debuggering-software should set the program-counter (PC) to the 
reset-handler's address. This can be done with OpenOCD just before a 
"resume".

Thank you very much for you reply
I will try it later and report what I get.

Thanks again.

Thank you Martin

By following you instruction ,I finaly made it work !

1.Modify the link script to put all the sections in ram

2.Set RUN_MODE to RAM_RUN in Makefile and make sure the linker link with 
the ram-run-link-script

3.Change the Reset_Handler to:

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void Reset_Handler(void)

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{

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/* SCB's VTOR register to the correct interrupt-vector-table address in ram */

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    #ifdef RAM_RUN

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    NVIC_SetVectorTable(NVIC_VectTab_RAM,0X0);

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    #endif

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/* FSMC Bank1 NOR/SRAM3 is used for the STM3210E-EVAL, if another Bank is 

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  required, then adjust the Register Addresses */

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  SystemInit_ExtMemCtl();

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  /* restore original stack pointer */

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  asm(" LDR r0, =_estack");

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  asm(" MSR msp, r0");

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  /* Initialize data and bss */

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   __Init_Data(); 

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  /* Call the application's entry point.*/

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  main();

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}

4.Change __Init_Data to:

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void __Init_Data(void)

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{

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  unsigned long *pulSrc, *pulDest;

4

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  #ifdef FLASH_RUN

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  /* Copy the data segment initializers from flash to SRAM */

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  pulSrc = &_sidata;

8

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  for(pulDest = &_sdata; pulDest < &_edata; )

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  {

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    *(pulDest++) = *(pulSrc++);

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  }

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  #endif

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  /* Zero fill the bss segment. */

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  for(pulDest = &_sbss; pulDest < &_ebss; )

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  {

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    *(pulDest++) = 0;

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  }

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}

5.Use the following openocd command:

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reset

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halt

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load_image PATH_TO_IMAGE 0x0 TYPE_OF_IMAGE

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reg pc 0x20000004

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resume