DMA
Question 1 |
A hard disk is connected to a 50 MHz processor through a DMA controller. Assume that the initial set-up of a DMA transfer takes 1000 clock cycles for the processor, and assume that the handling of the interrupt at DMA completion requires 500 clock cycles for the processor. The hard disk has a transfer rate of 2000 Kbytes/sec and average block transferred is 4 K bytes. What fraction of the processor time is consumed by the disk, if the disk is actively transferring 100% of the time?
Theory Explanation. |
Question 2 |
Which of the following requires a device driver?
Register | |
Cache | |
Main memory | |
Disk |
Question 2 Explanation:
Disk driver is software which enables communication between internal hard disk (or drive) and computer.
Question 3 |
Consider a computer system with DMA support, The DMA module is transferring one 8-bit character in one CPU cycle from a device to memory through cycle stealing at regular intervals. Consider a 2 MHz processor. If 0.5% processor cycles are used for DMA, the data transfer rate of the device is ______ bits per second.
80,000
|
Question 3 Explanation:
There are 3 questions to complete.