Microprocessor and Computer Architecture · Unit 9
Input Output and Data Transfer
Exam-focused notes for Input Output and Data Transfer (Microprocessor and Computer Architecture, BIT151): what the TU syllabus asks and how it has actually been tested, with 8 solved past questions from this unit.
What this unit covers
- I/O interface functions
- Isolated I/O and memory mapped I/O
- Advantages and disadvantages of I/O methods
- Direct Memory Access (DMA) process
- DMA controller role and operation
DMA controller role and operation
Explain the role of DMA controller in DMA operation. [5]
Direct Memory Access (DMA) is a technique that allows I/O devices to transfer data directly to/from main memory without involving the CPU for each byte/word of the transfer. The component that manages this process is the DMA Controller. --- The DMA controll...
Full solved answer →Isolated I/O and memory mapped I/O
Differentiate between I/O mapped (isolated) I/O and memory mapped I/O. [5]
--- - I/O devices are given a separate address space from memory. - Special I/O instructions (such as IN and OUT) are used to communicate with I/O devices. - The processor has separate control lines for memory and I/O operations (e.g., M/IO signal distingui...
Full solved answer →Explain the difference between isolated I/O and memory-mapped I/O? What are the advantages and disadvantages of each? [5]
Note: No specific curriculum notes were found for this topic. The following answer is based on standard computer organization and architecture principles, which are consistent with TU BSc CSIT syllabus. --- In isolated I/O, the I/O devices are given a separ...
Full solved answer →What is the difference between isolated 1/0 and memory-mapped I/0? What are the avantages and disadvantages of each? [5]
Note: No specific reference notes were found for this topic. The following answer is based on standard computer organization and architecture concepts, which align with the TU BSc CSIT curriculum. --- In isolated I/O, the I/O devices are given a separate ad...
Full solved answer →Direct Memory Access
Write short notes on (any two): a) DMA b) Flags in 8085 Microprocessor c) Instruction set. [5]
--- DMA is a technique that allows peripheral devices to transfer data directly to/from memory without involving the CPU for each byte of transfer. - Normally, the CPU handles all data transfers between I/O devices and memory, which wastes CPU time. - In DM...
Full solved answer →What is DMA? Explain the role of DMA controller in data transfer. [5]
DMA (Direct Memory Access) is a memory access technique that allows I/O devices to transfer data directly to or from main memory without the continuous involvement of the CPU. The CPU only initiates the transfer; the actual data movement is handled by a ded...
Full solved answer →What is DMA? Explain the basic DMA process. [5]
DMA (Direct Memory Access) is a technique that allows I/O devices to transfer data directly to or from main memory without the continuous involvement of the CPU. A special hardware unit called the DMA Controller manages this transfer, freeing the CPU to per...
Full solved answer →I/O interface functions
What is the function of I/O interface? Differentiate between Isolated I/O and memory mapped I/O. [5]
An I/O Interface acts as a bridge between the CPU/memory system and the peripheral (I/O) devices. Its main functions are: 1. Data Buffering - Temporarily holds data to compensate for the speed difference between the fast CPU and slow I/O devices. 2. Signal ...
Full solved answer →Make Unit 9 stick
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