Hi Angelo,
Making this its own thread.
Please have a look at the MQXUG.pdf in the MQX4.0/docs/mqx folder.
Search on _mem_extend for brief explanation of the function call.
Then in same folder open the MQXRM.pdf and search again for detailed information on the functino call.
Assumptions before making/implementing this call would be to have setup the FlexBus memory space for your external RAM.
Regards,
David