Define & Iniitialise flash variable in main

Question

Struggling with what is probably a simple command to define and initialise a flash variable in main.c (IAR Embedded Workbench / TI MSP430F)

I have a flash routine In a separate C file (Battery_Store.c) which takes in a variable (from main) and stores it in a set location. The flash routines function.

void Set_Battery_Store( unsigned int Battery_Status )
    {

            Flash_Start() ;
            Flash_Erase_Segment( (unsigned int *)&Battery_Status ) ;
            Flash_Write_Word( (unsigned int *)&Battery_Status, Battery_Status ) ;
            Flash_Finish() ;
    }

I define the variable and initialise it in the same C file

const volatile unsigned int Battery_Status @ 0x1070 = 1 ;

and in the .h

extern const volatile unsigned int Battery_Status ;

But of course every time I call Battery_Store from main (System_Flags.Battery_Status is a different variable handled in main). i.e.

Set_Battery_Store (System_Flags.Battery_Status)  ;

Battery_Status becomes 1 again, presumably because of the

const volatile unsigned int Battery_Status @ 0x1070 = 1 ;

How do I set and initialise Battery_Status from within main.c (and not within Battery_Store.c and Battery_Store.h) and have Battery_Store.c refer to it?

CL. CL. · Accepted Answer · 2017-11-27T15:48:07

The Battery_Status parameter of the Set_Battery_Store function is a parameter, so it lives on the stack. So when using &Battery_Status, this function never actually accesses any flash memory.

Give either the parameter or the global variable a different name.

Define & Iniitialise flash variable in main

1 Answers