Atmel Evaluation Kit AT91SAM9X25-EK AT91SAM9X25-EK Data Sheet

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SAM9X25 [DATASHEET]

11054E–ATARM–10-Mar-2014

The DMA Controller (DMAC) is an AHB-central DMA controller core that transfers data from a source peripheral to a 
destination peripheral over one or more AMBA buses. One channel is required for each source/destination pair. In the 
most basic configuration, the DMAC has one master interface and one channel. The master interface reads the data from 
a source and writes it to a destination. Two AMBA transfers are required for each DMAC data transfer. This is also known 
as a dual-access transfer.

The DMAC is programmed via the APB interface.

The DMAC embeds 8 channels.

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2 AHB-Lite Master Interfaces

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DMA Module Supports the Following Transfer Schemes: Peripheral-to-Memory, Memory-to-Peripheral, Peripheral-
to-Peripheral and Memory-to-Memory

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Source and Destination Operate independently on BYTE (8-bit), HALF-WORD (16-bit) and WORD (32-bit)

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Supports Hardware and Software Initiated Transfers

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Supports Multiple Buffer Chaining Operations

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Supports Incrementing/decrementing/fixed Addressing Mode Independently for Source and Destination

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Supports Programmable Address Increment/decrement on User-defined Boundary Condition to Enable Picture-in-
Picture Mode

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Programmable Arbitration Policy, Modified Round Robin and Fixed Priority are Available

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Supports Specified Length and Unspecified Length AMBA AHB Burst Access to Maximize Data Bandwidth

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AMBA APB Interface Used to Program the DMA Controller

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8 DMA Channels

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12 External Request Lines

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Embedded FIFO 

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Channel Locking and Bus Locking Capability