What Is Direct Memory Access (DMA) and How Does It Work?

Do you know what Direct Memory Access is and how it works?

If you dont know, then this post from MiniTool is what you need.

This post introduces its definition and how it works.

Whats more, you might also know its modes of operation.

This post fromMiniToolis mainly talking about DMA.

The Definition of Direct Memory Access

First of all, what is Direct Memory Access?

Direct Memory Access can be abbreviated to DMA, which is a feature of computer systems.

DMA is also used for on-chip data transfer in multi-core processors.

Direct Memory Access can also be used for memory to memory to copy or move data in memory.

DMA is important in connection-on-chip and memory computing architectures.

Then how does Direct Memory Access work?

Standard Direct Memory Access (also called third-party DMA) adopts a DMA controller.

The DMA controller can produce memory addresses and launch memory read or write cycles.

It covers multiple hardware registers that can be read and written by the CPU.

Then the CPU commands the peripheral machine to begin data transfer.

Then the Direct Memory Access controller offers addresses and read/write control lines to the system memory.

Direct Memory Access works differently in different modes of operation.

In burst mode, the full data block is transmitted in a continuous sequence.

This mode is also called Block Transfer Mode.

These two signals control the interface between the CPU and the DMA controller.

This is also called hidden DMA data transfer mode.