/* Define the memory regions: Flash and RAM */
MEMORY
{
  FLASH (rx)  : ORIGIN = 0x08000000, LENGTH = 64K
  RAM   (rwx) : ORIGIN = 0x20000000, LENGTH = 20K
}

/* Define entry point (usually the reset handler defined in startup code) */
ENTRY(Reset_Handler)

/* Define the sections of the program */
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 variables) */
    _etext = .;                 /* Mark the end of text section */
  } > FLASH

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

  /* Uninitialized data section, placed in RAM but not stored in Flash */
  .bss :
  {
    _sbss = .;                  /* Start of BSS */
    *(.bss)                     /* Uninitialized data */
    *(COMMON)                   /* Common symbols (zero-initialized) */
    _ebss = .;                  /* End of BSS */
  } > RAM

  /* Stack section */
  ._stack : 
  {
    . = ALIGN(8);               /* Align to 8-byte boundary */
    _estack = .;                /* End of stack (top of the stack) */
    . = . + 2048;               /* Reserve 2 KB for stack */
    _sstack = .;                /* Start of stack */
  } > RAM

  /* Heap section */
  .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);