IGNOU NOTES

MCS-012 Computer Organisation and Assembly Language programming What is the advantage of DMA? Devices that use DMA provide one significant advantage over devices that do not. What is this advantage? A) Devices that can use DMA are designed for low power consumption, making them perfect for laptops. B) DMA-capable hard drives have much higher seek times than those drives that don’t support DMA. C) A device that supports DMA supports faster CPUs than those devices without DMA support. D) A DMA-capable device can communicate directly with memory, bypassing the CPU. https://www.professormesser.com/free-a-plus-training/a-plus-pop-quizzes/what-is-the-advantage-of-dma/ Direct memory access (DMA) is a method that allows an input/output (I/O) device to send or receive data directly to or from the main memory, bypassing the CPU to speed up memory operations. The process is managed by a chip known as a DMA controller (DMAC). A computer's system resource tools are used for communication...

MCS-012 Computer Organisation and Assembly Language Programming                                  Basics and Overview of Flip Flops A flip flop is an electronic circuit with two stable states that can be used to store binary data. The stored data can be changed by applying varying inputs. Flip-flops and latches are fundamental building blocks of digital electronics systems used in computers, communications, and many other types of systems. Flip-flops and latches are used as data storage elements. It is the basic storage element in sequential logic. But first, let’s clarify the difference between a latch and a flip-flop.                                                         Flip flop v/s Latch The basic difference between a latch and a flip-flop is a gating o...

                       MCS-012 Computer organisation and assembly Language An interrupt is a signal sent to the processor that interrupts the current process. It may be generated by a hardware device or a software program. A hardware interrupt is often created by an input device such as a mouse or keyboard. For example, if you are using a word processor and press a key, the program must process the input immediately. Typing "hello" creates five interrupt requests, which allows the program to display the letters you typed. Similarly, each time you click a mouse button or tap on a touchscreen, you send an interrupt signal to the device. An interrupt is sent to the processor as an interrupt request, or IRQ. Each input device has a unique IRQ setting, or priority. This prevents conflicts and ensures common input devices, such as keyboards and mice, are prioritized. Software interrupts are used to handle errors and...

                  MCS-012 Computer organisation and assembly Language In the large-scale-digital systems, a single line is required to carry on two or more digital signals – and, of course! At a time, one signal can be placed on the one line. But, what is required is a device that will allow us to select; and, the signal we wish to place on a common line, such a circuit is referred to as multiplexer. The function of a multiplexer is to select the input of any ‘n’ input lines and feed that to one output line. The function of a de-multiplexer is to inverse the function of the multiplexer and the shortcut forms of the multiplexer. The de-multiplexers are mux and demux. Some multiplexers perform both multiplexing and de-multiplexing operations. The main function of the multiplexer is that it combines input signals, allows data compression, and shares a single transmission channel. What is a Multiplexer and D...

                                      MCS-012 Computer organisation and assembly Language RISC Machine Features There is some controversy concerning what is or is not a RISC processor. The debate centers upon whether to classify a machine as RISC, as opposed to CISC, by architectural differences such as an abundance of registers or by performance measures such as performance of benchmark programs. In this section, we mention a number of architectural features commonly associated with RISC machines. Small, Simpler Instruction Set and Few Addressing Modes Small ,   simple   and   few   are relative terms. Instruction set sizes are typically less than 150. Four or fewer addressing modes are common, although some processors have more. Instruction set formats tend to be fixed in size, in contrast to variable length instruction formats of CISC machines. The num...

                                                 MCS-012 Computer organisation and assembly Language What is Pipelining? Pipelining is the process of accumulating instruction from the processor through a pipeline. It allows storing and executing instructions in an orderly process. It is also known as  pipeline processing . Pipelining is a technique where multiple instructions are overlapped during execution. Pipeline is divided into stages and these stages are connected with one another to form a pipe like structure. Instructions enter from one end and exit from another end. Pipelining increases the overall instruction throughput. In pipeline system, each segment consists of an input register followed by a combinational circuit. The register is used to hold data and combinational circuit performs operations on it. The output of combination...

                             MCS-012 Computer organisation and assembly Language What is RAID? RAID is an acronym for Redundant Array of Independent (or Inexpensive) Disks. In fact, RAID is the way of combining several independent and relatively small disks into a single storage of a large size. The disks included into the array are called array members. The disks can be combined into the array in different ways which are known as  RAID levels . Each of RAID levels has its own characteristics of: Fault-tolerance  which is the ability to survive of one or several disk failures. Performance  which shows the change in the read and write speed of the entire array as compared to a single disk. The capacity  of the array which is determined by the amount of user data that can be written to the array. The array capacity depends on the RAID level and does not always match the sum of t...