/*
 * Filename: linker.ld
 * Micro-Controller: stm32f103c8t6
 * Cortex-M3 and Cortex-M4 only need to be 4byte aligned where as
 * other's might need 8byte or something different.
 *
 * The M3/M4 are ARMv7 and ARMv7E-M respectively.
 */


/*
 * Program Entry Point:
 *      This part is put into the elf file header.
 */
ENTRY(Reset_Handler)

/* Highest address of user mode stack */
_estack  = ORIGIN(RAM) + LENGTH(RAM); /* end of "RAM" Ram type memory */

/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0x200; /* required amount of heap. */
_Min_Stack_Size = 0x400; /* required amount of stack. */



/*
 * FORMAT:
 * R: Read only section.
 * W: Read/Write section.
 * X: Executable section.
 * A: Allocation section.
 * I: Initialized section.
 * !: Invert following attribute.
 */


/*
 * MEMORY Format:
 *  name [(attr)] : ORIGIN = origin, LENGTH = len
 */

/* You will want to change these values to match your uC.*/
MEMORY
{
    FLASH(rx): ORIGIN = 0x08000000, LENGTH = 64K
    SRAM(rwx): ORIGIN = 0x20000000, LENGTH = 20K
}

/* VMA: virtual memory address.*/
/* LMA: Load memory address. */

floating_point = 0;
SECTIONS
{

    /* Code section, mapped to Flash memory */
    .text :
    {
        KEEP(*(.isr_vector))    /* Vector table, which must be at the beginning of Flash*/
        *(.text)                /* All code goes here */
        *(.rodata)              /* Read-only data (e.g., const vars) */
        _etext = .;             /* Mark the end of text section */
    } > FLASH

    /* Initialized data section, copied from Flash to RAM on startup. */
    .data :
    {
        _sdata = .;                 /* Start of data section */
        *(.data)                    /* Initialized data */
        _edata = .;                 /* End of data section */
    } > RAM AT > FLASH

    /* BSS: Placed in SRAM memory types. */
    /* Holds all uninitialized globals and static variables.*/ 
    .bss :
    {
        _sbss = .;                  /* Start of BSS */
        *(.bss)                     /* Uninitialized data */
        *(COMMON)                   /* Common symbols (zero-init) */
        _ebss = .;                  /* End of BSS */
    } > RAM

    /* Stack Section: Sizes known at compile time. */
    ._stack :
    {
        . = ALIGN(8);               /* Align to 8-byte boundry */
        _estack = .;                /* End of stack (top of the stack) */
        . = . + 2048;               /* Reserve 2KB for stack */
        _sstack = .;                /*Start of stack */
    } > RAM

    /* Heap Section: Used for dynamic memory allocation. */
    .heap :
    {
        _sheap = .;                 /* Start of heap */
        . = . + 2048;               /* Reserve 2 KB for heap */
        _eheap = .;                 /* End of heap */
    } > RAM
}

/* Provide symbols to be used in the startup code */
PROVIDE(_stack_start = _sstack);
PROVIDE(_stack_end = _estack);
PROVIDE(_heap_start = _sheap);
PROVIDE(_heap_end = _eheap);