C280x cmd file - const definition in RAM

Hi,

Are you confirming the above implementation? Do check:

Regards,

Gautam

Here are some details. The MCU I used is TMS320F2806, and I user '#define' to define a constant previously. But my colleague requires to define this value in RAM, something like the method mentioned above. His word is "the nodeId shall be a constant linked at specific data address section used only for its own, like this we can change it during the internal flash programming. ", but I am not sure about it.

Actually I tested 2 method:

1. Define like the method mentioned above, it works with emulator, but the value changed without emulator. As I doubted, the value might not be fixed even if defined as 'const volatile' in RAM, but I am not sure. That is the reason I want to check with expert.
2. Define the value in RAM, and assign value during initialization process. It works well with or without emulator. But I do not think it has advantage comparing to method of '#define). The method is listed below.

1.    f2806.cmd

MEMORY

{

PAGE 0:    /* Program Memory */

           /* Memory (RAM/FLASH/OTP) blocks can be moved to PAGE1 for data allocation */

   nodeIdAddr  : origin = 0x008000, length = 0x000002

   RAML0       : origin = 0x008002, length = 0x00FFFE     /* on-chip RAM block L0 */

 }

/* Allocate sections to memory blocks.

   Note:

         codestart user defined section in DSP28_CodeStartBranch.asm used to redirect code

                   execution when booting to flash

         ramfuncs  user defined section to store functions that will be copied from Flash into RAM

*/

SECTIONS

{

   /* Allocate uninitalized data sections: */

   nodeIdFile          : > nodeIdAddr   PAGE = 0

}

 2.    Variable Definition

#pragma DATA_SECTION(ID_BOARD, "nodeIdFile")

volatile uint32 ID_BOARD;

 3.    Reference definition

extern volatile uint32 ID_BOARD;

 4.    Initiialization

       ID_BOARD = 100000UL;