.. index:: ram, free ram, random access memory, maximum ram, tick word

.. _ram:

Random Access Memory
====================

Free Ram ?
----------
Ram starts at $2000000 and grows upwards to the physical limit. My STM32F051 has 8KB Ram therefore the maximum is at $20002000

Mecrisp will use a certain amount ($38C or 908 decimal bytes in this example).

Find The Start of Free Ram
^^^^^^^^^^^^^^^^^^^^^^^^^^
::

 compiletoram here hex. 2000038C  ok.

Create The Word "freeram"
^^^^^^^^^^^^^^^^^^^^^^^^^
::

 : freeram ( -- )
   flashvar-here 4 -
   compiletoram here
   - . ." Bytes " 
 ;

"freeram" Word Dictionary Entry
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
::

 Address: 2000038C Link: 000000C0 Flags: 00000000 Code: 2000039A Name: freeram

.. note:: Tick(') also shows markers memory location

::

 ' freeram hex. 2000039A  ok.

Free Ram Start (after "freeram" has been created)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
::

 compiletoram here hex. 200003D0  ok.

Find The End of Free Ram
^^^^^^^^^^^^^^^^^^^^^^^^
::

 flashvar-here 4 - 

A Word to Find Free Ram
^^^^^^^^^^^^^^^^^^^^^^^
"freeram" already created above
::

 : freeram ( -- )
   flashvar-here 4 -
   compiletoram here
   - . ." Bytes " 
 ;

::

 freeram

 freeram 7028 Bytes  ok.