4: Strategies and Interface I/O
- Page ID
- 14826
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Learning Objectives
At the end of this unit, the learners will
- Explain the Strategies of Interface I/O
- Distinguish between handshaking and buffering
- Understand the programmed IO mode of data transfer
- Describe a DMA transfer.
This section introduces the learners to the strategies of I/O interfaces. They include: polled, interrupt driven and DMA.
- 4.1: Fundamentals I/O- handshake and buffering
- This section introduces the learner to the various strategies used in I/O interfaces and other operations possible on an interface
- 4.2: Mechanisms of interruption- recognition of vector, and interrupt priority
- The following section introduces the learner to Interruptions that occur in Programmed I/O
- 4.3: Direct Memory Access (DMA)
- This section introduces the learners to the DMA programmed I/O which provides access to the microprocessor between devices operating at different speeds
- 4.4: Unit 4 Summary
- At the end of this unit, the learners will be conversant with the strategies of I/O interfaces. This involves accessibility of devices connected to the processor and where I/O transfers must take place between them and the processor. the various access methods, e.g. polling, interrupt and DMA. The interrupt process is also learned in this section.


