Datasheet
31
SAM3S [SUMMARY]
6500ES–ATARM–11-Feb-13
9. Memories
9.1 Embedded Memories
9.1.1 Internal SRAM
The ATSAM3S4 product (256-Kbyte internal Flash version) embeds a total of 48 Kbytes high-speed SRAM.
The ATSAM3S2 product (128-Kbyte internal Flash version) embeds a total of 32 Kbytes high-speed SRAM.
The ATSAM3S1 product (64-Kbyte internal Flash version) embeds a total of 16 Kbytes high-speed SRAM.
The SRAM is accessible over System Cortex-M3 bus at address 0x2000 0000.
The SRAM is in the bit band region. The bit band alias region is mapped from 0x2200 0000 to 0x23FF FFFF.
9.1.2 Internal ROM
The SAM3S product embeds an Internal ROM, which contains the SAM Boot Assistant (SAM-BA), In Application
Programming routines (IAP) and Fast Flash Programming Interface (FFPI).
At any time, the ROM is mapped at address 0x0080 0000.
9.1.3 Embedded Flash
9.1.3.1 Flash Overview
The Flash of the ATSAM3S4 (256-Kbytes internal Flash version) is organized in one bank of 1024 pages (Single plane)
of 256 bytes.
The Flash of the ATSAM3S2 (128-Kbytes internal Flash version) is organized in one bank of 512 pages (Single plane) of
256 bytes.
The Flash of the ATSAM3S1 (64-Kbytes internal Flash version) is organized in one bank of 256 pages (Single plane) of
256 bytes.
The Flash contains a 128-byte write buffer, accessible through a 32-bit interface.
9.1.3.2 Flash Power Supply
The Flash is supplied by VDDCORE.
9.1.3.3 Enhanced Embedded Flash Controller
The Enhanced Embedded Flash Controller (EEFC) manages accesses performed by the masters of the system. It
enables reading the Flash and writing the write buffer. It also contains a User Interface, mapped on the APB.
The Enhanced Embedded Flash Controller ensures the interface of the Flash block with the 32-bit internal bus. Its 128-bit
wide memory interface increases performance.
The user can choose between high performance or lower current consumption by selecting either 128-bit or 64-bit
access. It also manages the programming, erasing, locking and unlocking sequences of the Flash using a full set of
commands.
One of the commands returns the embedded Flash descriptor definition that informs the system about the Flash
organization, thus making the software generic.
9.1.3.4 Flash Speed
The user needs to set the number of wait states depending on the frequency used.
For more details, refer to the AC Characteristics sub section in the product Electrical Characteristics Section.