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97 The static allocation area, located at the beginning of RAM, includes all module-level variables defined by your application and all statically allocated system variables. This includes the task stacks that are statically allocated by your application. The task stack for Main() occupies all of the RAM between the end of the static allocation area and the heap. The stack pointer for all task stacks is initialized to the end of the task stack space and moves toward lower RAM addresses as it is used. By default, the Heap Limit is set at 512 bytes from the end of RAM. For devices with external RAM, the heap is located at the end of external RAM as determined at startup. The heap will not grow beyond the Heap Limit. When the heap is exhausted, further allocation attempts will fail, possibly resulting in malfunctioning of your application. The heap is used for storing most RAM- based strings (but not BoundedString or fixed-string types) including strings that are returned by functions you define in your application and System Library functions that return strings. Additionally, on devices which have Program Memory in internal Flash memory, when a Program Memory write operation is performed a temporary buffer is allocated from the heap. The size of this buffer is equal to the Flash page size for the microcontroller, typically 256 bytes. This additional temporary use of heap space must be considered if your application performs write operations on Program Memory. Lastly, the System Library function System.Alloc() may be used by your application to allocate memory from the heap. All of these uses must be considered when determining how much heap space is needed by your application. The function System.HeapHeadRoom() may be helpful for determining the minimum heap size for your application. If the default heap size is insufficient for your application, you can specify the Heap Limit setting in several different ways, each of which may be useful in different circumstances. Perhaps the simplest method of setting the Heap Limit is to specify the desired size for the Main() task stack. This can be done using the directive Option MainTaskStackSize in your Main module or by using the compiler option –-main- task-stack-size. In both cases, the Heap Limit is set by adding the specified size to the address of the end of the static allocation area.