Atmel Evaluation Kit AT91SAM9X25-EK AT91SAM9X25-EK データシート

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SAM9X25 [DATASHEET]

11054E–ATARM–10-Mar-2014

The Bus Matrix implements a multi-layer AHB, based on the AHB-Lite protocol, that enables parallel access paths 
between multiple AHB masters and slaves in a system, thus increasing the overall bandwidth. The Bus Matrix 
interconnects up to 16 AHB masters to

 

up to 16 AHB slaves. The normal latency to connect a master to a slave is one 

cycle except for the default master of the accessed slave which is connected directly (zero cycle latency). 

The Bus Matrix user interface is compliant with ARM Advanced Peripheral Bus and provides a Chip Configuration User 
Interface with Registers that allow the Bus Matrix to support application specific features.

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12-layer Matrix, handling requests from 11 masters

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Programmable Arbitration strategy

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Fixed-priority Arbitration

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Round-Robin Arbitration, either with no default master, last accessed default master or fixed default master

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Burst Management 

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Breaking with Slot Cycle Limit Support

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Undefined Burst Length Support

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One Address Decoder provided per Master

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Three different slaves may be assigned to each decoded memory area: one for internal ROM boot, one for 
internal flash boot, one after remap

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Boot Mode Select

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Non-volatile Boot Memory can be internal ROM or external memory on EBI_NCS0

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Selection is made by General purpose NVM bit sampled at reset

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Remap Command

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Allows Remapping of an Internal SRAM in Place of the Boot Non-Volatile Memory (ROM or External Flash)

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Allows Handling of Dynamic Exception Vectors