Direct Memory Access (DMA) Introduction
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SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
DMA Controller
11.1 Direct Memory Access (DMA) Introduction
The DMA controller transfers data from one address to another, without CPU intervention, across the
entire address range. For example, the DMA controller can move data from the ADC conversion memory
to RAM.
Devices that contain a DMA controller can have up to eight DMA channels available. Therefore,
depending on the number of DMA channels available, some features described in this chapter are not
applicable to all devices. See the device-specific data sheet for the number of channels that are
supported.
Using the DMA controller can increase the throughput of peripheral modules. It can also reduce system
power consumption by allowing the CPU to remain in a low-power mode, without having to awaken to
move data to or from a peripheral.
DMA controller features include:
•
Up to eight independent transfer channels
•
Configurable DMA channel priorities
•
Requires only two MCLK clock cycles per transfer
•
Byte, word, or mixed byte and word transfer capability
•
Block sizes up to 65535 bytes or words
•
Configurable transfer trigger selections
•
Selectable-edge or level-triggered transfer
•
Four addressing modes
•
Single, block, or burst-block transfer modes
The DMA controller block diagram is shown in