Datasheet

SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
382
23. External Memory Bus
23.1 Description
The external memory bus allows external devices connection to the various embedded memory controllers of the
microcontroller. The external memory bus handles control, address and data bus of each embedded memory
controllers. The SAM3X embeds a Static Memory/NAND Flash/ECC Controller (SMC/NFC/ECC) and a SDR-
SDRAM Controller (SDR-SDRAMC). Furthermore, the external memory bus handles data transfers with up to
eight external devices, each assigned to eight address spaces. Data transfers are performed through a 8-bit or 16-
bit data bus, an address bus of up to 24 bits, up to eight chip select lines (NCS[7:0]) and several control pins that
are generally multiplexed between the different embedded memory controllers.
23.2 Embedded Characteristics
 Only present on 144-pin SAM3X and 217-pin SAM3X8H
(1)
versions
 Managing SMC, NAND Flash and SDR-SDRAM Controller accesses offering:
 Up to 8 configurable chip selects
 Programmable timing on a per chip select basis
 16 Mbyte Address Space per Chip Select
 8- or 16-bit Data Bus
 Word, Halfword, Byte Transfers
 Byte Write or Byte Select Lines
 Programmable Setup, Pulse and Hold Time for Read Signals per Chip Select
 Programmable Setup, Pulse and Hold Time for Write Signals per Chip Select
 Programmable Data Float Time per Chip Select
 External Wait Request
 Automatic Switch to Slow Clock Mode
 Asynchronous Read in Page Mode Supported: Page Size Ranges from 4 to 32 bytes
 NAND Flash Controller supporting NAND Flash with Multiplexed Data/Address buses
 Supports SLC NAND Flash technology
 Supports Hardware Error Correcting Code (ECC), 1-bit error correction, 2-bit error detection
 Detection and Correction by Software
 Supports SDRAM with 8- or 16-bit Data Path (217-pin SAM3X8H
(1)
)
Note: 1.This device is not commercially available. Mounted only on the SAM3X-EK evaluation kit.