ohjelmamuistin

Ohjelmamuisti, often referred to as program memory or code memory, is a fundamental concept in computer science and computer architecture. It refers to the portion of a computer's memory that is dedicated to storing the executable instructions of a program. When a program is launched, its machine code instructions are loaded from a storage device, such as a hard drive or SSD, into the computer's main memory, where the CPU can access them directly. This area of memory is specifically designated for these instructions and is distinct from other memory regions like data memory, which stores variables and other runtime data.

The CPU fetches instructions sequentially from the ohjelmamuisti, decodes them, and then executes them. This process forms the core of how a computer runs software. The size and organization of ohjelmamuisti are critical for program performance. Efficient loading and access to these instructions are paramount for smooth operation. In modern systems, memory management units (MMUs) play a crucial role in managing access to ohjelmamuisti, ensuring that programs can only access their allocated code space and preventing interference with other processes or the operating system. The concept of ohjelmamuisti is tied to the fetch-decode-execute cycle and is essential for understanding how software is executed at a low level.