/* Linker script for a system with 128KB RAM starting at 0x10000 */
MEMORY
{
    RAM (wx) : ORIGIN = 0x0000, LENGTH = 128K
}

SECTIONS
{
    /* Place code and readonly data at the beginning of RAM */
    .text :
    {
        *(.text*)
        *(.rodata*)
    } > RAM

    /* Place initialized data right after the .text section */
    .data : 
    {
        . = ALIGN(4);
        *(.data*)
    } > RAM

    /* Uninitialized data (BSS) follows initialized data */
    .bss :
    {
        . = ALIGN(4);
        __bss_start = .;
        *(.bss*)
        *(COMMON)
        . = ALIGN(4);
        __bss_end = .;
    } > RAM

    /* Define heap start right after bss */
    . = ALIGN(4);
    __heap_start = .;
    PROVIDE(heap_start = __heap_start);

    /* Leave space for the heap by not explicitly defining its end */
    /* The heap grows towards the stack */

    /* Reserve space for the stack at the end of RAM */
    /* Let's say we want a 16KB stack */
    . = ALIGN(4);
    __stack_size = 16K; /* Size of the stack */
    __stack_top = ORIGIN(RAM) + LENGTH(RAM); /* Top of the stack */
    __stack_start = __stack_top - __stack_size; /* Start of the stack */
    .stack (NOLOAD) :
    {
        . = __stack_start;
        . += __stack_size; /* Allocate space for the stack */
        . = ALIGN(4);
    } > RAM

    PROVIDE(__stack = __stack_top);
    PROVIDE(stack_top = __stack_top);
    PROVIDE(stack_start = __stack_start);
    
    /* Heap end is dynamically located at the start of the stack */
    __heap_end = __stack_start;
    PROVIDE(heap_end = __heap_end);

    /* End of RAM usage */
    . = ALIGN(4);
    _end = .;
    PROVIDE(end = _end);
}