1. Which of the following provides an efficient method for transferring data from a peripheral to memory?
A. DMA controller
B. serial port
C. parallel port
D. dual port
Answer: A
The DMA controller or direct memory access controller provides an efficient method for transferring data from the peripheral to the memory.
2. Which of the following can be adopted for the systems which do not contain a DMA controller for data transmission?
A. counter
B. timer
C. polling
D. memory
Answer: C
The polling and interrupt help for data transmission for the systems which do not have a DMA controller.
3. Which of the following have low-level buffer filling?
A. output
B. peripheral
C. DMA controller
D. input
Answer: C
The DMA controller can initiate and control the bus access between I/O devices and memory, and also between two different memory areas. Therefore, the DMA controller can act as a hardware implementation of low-level buffer filling or emptying the interrupt.
4. How many classifications of DMA controllers are made based on the addressing capability?
A. 2
B. 3
C. 4
D. 5
Answer: B
There are three classifications for the DMA controllers based on the address capability. These are 1D, 2D, and 3D.
5. How many address registers are there for the 1D type DMA controller?
A. 1
B. 2
C. 3
D. 4
Answer: A
The 1D controller only has a single address register whereas the 2D controller has two address register and the 3D controller have three or more address register.
6. Which of the following generic DMA controllers contains a base address register and an auto-incrementing counter?
A. address bus
B. data bus
C. bus requester
D. address generator
Answer: D
The generic controller has several components associated with it for controlling the operation and one such is the address generator. It consists of the base address register and an auto-incrementing counter which increment the address after every transfer.
7. Which of the following is used to transfer the data from the DMA controller to the destination?
A. data bus
B. address bus
C. request bus
D. interrupt signal
Answer: A
The data bus is used for the transmission of data from the DMA controller to the destinal. The DMA controller can directly select the peripheral in some cases in which the data transfer is made from the peripheral to the memory.
8. Which of the following is used to request the bus from the main CPU?
A. data bus
B. address bus
C. bus requester
D. interrupt signal
Answer: C
The bus requester requests the bus from the main CPU. In earlier design, the processor bus does not support the multi-master system and there were no bus request signals. In such cases, the processor clock was extended.
9. Which signal can identify the error?
A. data bus
B. address bus
C. bus requester
D. interrupt signal
Answer: D
The interrupt signal can identify the error that occurred in the DMA controller. This makes the processor reprogram the DMA controller for a different transfer.
10. Which signal allows the DMA controller to select the peripheral?
A. local peripheral control
B. global peripheral control
C. address bus
D. data bus
Answer: A
The local peripheral control allows the DMA controller to select the peripheral.
