DMA controller on bus in ARM Architecture - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the sentence to describe the role of a DMA controller on a bus.

ARM Architecture

A DMA controller allows devices to transfer data directly to memory without involving the [1].

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ACPU

BALU

CGPU

DCache

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing DMA with GPU operations

Thinking DMA involves the cache directly

The DMA controller handles data transfers directly, freeing the CPU from managing these operations.

2fill in blank

medium

Complete the sentence to explain how a DMA controller interacts with the bus.

ARM Architecture

The DMA controller takes control of the [1] to transfer data between devices and memory.

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Asystem bus

Baddress bus

Ccontrol bus

Ddata bus

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing only data bus or address bus separately

Confusing control bus with the whole system bus

The system bus includes address, data, and control lines, which the DMA controller uses to manage transfers.

3fill in blank

hard

Fix the error in the description of DMA operation.

ARM Architecture

DMA controller transfers data by [1] the CPU to access memory directly.

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Ainterrupting

Busing

Cbypassing

Dreplacing

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking DMA uses the CPU actively

Assuming DMA replaces the CPU

DMA works by bypassing the CPU to allow direct memory access, improving efficiency.

4fill in blank

hard

Fill both blanks to complete the DMA transfer process description.

ARM Architecture

The DMA controller [1] the bus and [2] data between the device and memory.

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Aarbitrates

Bmonitors

Ctransfers

Drequests

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing monitoring with arbitrating

Mixing up requesting and transferring

The DMA controller first arbitrates for control of the bus, then transfers data directly.

5fill in blank

hard

Fill all three blanks to describe DMA controller signals.

ARM Architecture

The DMA controller uses [1] to request bus access, [2] to indicate transfer completion, and [3] to transfer data.

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ABus Request (BR)

BBus Grant (BG)

CData lines

DInterrupt Request (IRQ)

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing Bus Grant with Bus Request

Confusing Interrupt Request with Bus Grant

BR is used to request the bus, IRQ signals transfer completion, and data lines carry the actual data.