Memory Mapped I/O
Memory Mapped I/O (MMIO) is a technique in computer architecture where input/output (I/O) devices are mapped into the system's memory address space, allowing the CPU to access device registers and buffers using standard memory read/write instructions instead of specialized I/O instructions. This approach simplifies programming by treating I/O operations similarly to memory accesses, enabling direct manipulation of hardware through memory addresses. It is commonly used in modern processors and embedded systems for efficient communication with peripherals like graphics cards, network interfaces, and storage controllers.
Developers should learn and use Memory Mapped I/O when working on low-level systems programming, embedded systems, or device drivers, as it provides a unified memory model that reduces complexity and improves performance by eliminating the need for separate I/O instructions. It is particularly useful in scenarios requiring fast, direct hardware interaction, such as in real-time applications, operating system kernels, or custom hardware interfaces, where precise control over device registers is essential for functionality and optimization.