DMA Controller (8257) » Exercise – 1
1. DMA stands for :
(a) Direct memory allocation
(b) Direct memory access
(c) Distinct memory allocation
(d) Distinctmemory access
2. Which is the fastest DMA mode ?
(a) Cycle steal
(b) Hidden mode
(c) Block transfer
(d) None of these
3. 8257 can interface with ………….. IO devices.
(a) 2
(b) 3
(c) 4
(d) 5
4. Each of the channel in 8257 consists of :
(a) 14-bit counter resister
(b) 16-bit counter resister
(c) Both (a) & (b)
(d) None of these
5. How many clock cycles are used by 8257 to transfer a byte of data ?
(a) 2 clock cycle
(b) 4 clock cycle
(c) 6 clock cycle
(d) 8clock cycle
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