DMA CONTROLLER
ARCHITECTURE OF 8085
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Acknowledge signal
|
|
|
Interrupt signal
|
|
|
WMFC signal
|
|
|
None of the mentioned
|
Detailed explanation-1: -The controller notifies the DSP processor that it is ready for a transfer. Then the processor relinquishes control of its external memory bus and grants the control of the bus to the DMA controller. The DMA controller then transfers the specified amount of data and signals the processor upon completion of the transfer.
Detailed explanation-2: -Once the data transfer completes, the DMA raises an interrupt to notify the processor about completing the data transfer function. The processor can control the bus again and begin processing where it left off.
Detailed explanation-3: -After completion of data transfer, it disables the bus request signal and CPU disables the bus grant signal thereby moving control of buses to the CPU. When an I/O device wants to initiate the transfer then it sends a DMA request signal to the DMA controller, for which the controller acknowledges if it is free.
Detailed explanation-4: -the processor. Once the operation is complete, the processor is notified. This notification is done by using an interrupt mechanism.