Program stored memory

This can happen because there are no statements that require the addresses of a or b. On higher optimization settings, the compiler can delete all your code and replace with a return 0. The variables a and b are not changed.

The variable c is changed but not used by any other statements. Your program has no effect nothing is printed, there are no external actions like writing to hardware. Thus your program can be reduced down to return 0;. In general, processor instructions are placed in a segment you will call "code memory". Constants, like numbers, can be placed into a Read-Only segment or in the Code Segment.

All you can guarantee, is that the code will not write to the Read-Only segment. Data Memory is different. These memory areas can be placed anywhere, as long as the memory has read and write capabilities. Memory organization is more complicated than having Code, Stack and Heap. In the embedded systems world, memory can be place in non-standard locations and there may be a need to have more detailed memory segments so they can be placed in different areas.

For example, an embedded system may want to place the constants into Flash so that they can be changed easily even though they may be more efficiently accessed in the Code Segment.

Some code may want to be placed into the Boot Area of the processor which is programmed by the processor manufacturer. Some embedded systems may have non-volatile memory e.

Trust in your compiler to place code, data and variables in the most efficient areas as possible. Your compiler knows your platform and will make the best decisions for you.

If you need to change your compiler's settings, you can, but you should really know what you are doing and why you need to change them. Embedded systems are different and depend on the hardware devices. Code may be run from flash because the platform has minimal RAM. Some may store the code compressed in a serial access read-only device and have to decompress into RAM before executing. In these situations, the compilers are configured for these specializations.

So, trust in your compiler and let it place the code and data into the correct segments and locations. Modifying the control sequence in a wired-type computer can be challenging and time consuming. In most cases, it would require wiring of equipment which might not produce economical results due to its high cost or difficult construction altogether — especially if one wants versatile designs with alternative plug ins boards for modifying certain aspects only rather than overhauling everything at once.

The degree by which you modify your programme will depend entirely on what kind of variation s desired: adding more features is easy enough but taking them away again may take some doing. The idea of using binary math to store information was introduced by John von Neumann in the late s. He proposed that programs be electronically stored within a memory device so they can change based on intermediate computational results, which are saved at different times during execution for later use if necessary.

The stored program concept means that data and instructions are both logically the same, meaning they can be stored in memory. It may seem confusing at first glance: what does storing programs mean if not executing them from without? However this idea has been key to our inventions such as early microprocessors where CPUs were designed. Many of the programs we use on a daily basis, such as Google and Microsoft Word, are stored program concepts.

What does this mean? Take some time out of your day to think about just. You must be logged in to post a comment. Contents 1 What is stored program control concept?

See also Who does apple's advertising? See more articles in category: Digital. Text segment i. Initialized data segment 3.

Uninitialized data segment bss 4. Heap 5. Stack A typical memory layout of a running process 1. Text Segment: A text segment, also known as a code segment or simply as text, is one of the sections of a program in an object file or in memory, which contains executable instructions. As a memory region, a text segment may be placed below the heap or stack in order to prevent heaps and stack overflows from overwriting it.

Usually, the text segment is sharable so that only a single copy needs to be in memory for frequently executed programs, such as text editors, the C compiler, the shells, and so on. Also, the text segment is often read-only, to prevent a program from accidentally modifying its instructions. A data segment is a portion of the virtual address space of a program, which contains the global variables and static variables that are initialized by the programmer.

Note that, the data segment is not read-only, since the values of the variables can be altered at run time. This segment can be further classified into the initialized read-only area and the initialized read-write area. For instance, a variable declared static int i; would be contained in the BSS segment. For instance, a global variable declared int j; would be contained in the BSS segment. Stack: The stack area traditionally adjoined the heap area and grew in the opposite direction; when the stack pointer met the heap pointer, free memory was exhausted.

With modern large address spaces and virtual memory techniques they may be placed almost anywhere, but they still typically grow in opposite directions.

The stack area contains the program stack, a LIFO structure, typically located in the higher parts of memory.