– Each Master can be assigned a priority between 0 and 7
• Address Decoder provides selection for
– Eight external 256-Mbyte memory areas
– Four internal 1-Mbyte memory areas
– One 256-Mbyte embedded peripheral area
• Boot Mode Select Option
– Non-volatile Boot Memory can be internal or external
– Selection is made by BMS pin sampled at reset
• Abort Status Registers
– Source, Type and all parameters of the access leading to an abort are saved
• Misalignment Detector
– Alignment checking of all data accesses
– Abort generation in case of misalignment
• Remap command
– Provides remapping of an internal SRAM in place of the boot NVM
3.7
External Bus Interface
• Integrates three External Memory Controllers:
– Static Memory Controller
– SDRAM Controller
– Burst Flash Controller
• Additional logic for NAND Flash/SmartMedia and CompactFlash support
• Optimized External Bus:
– 16- or 32-bit Data Bus
– Up to 26-bit Address Bus, up to 64-Mbytes addressable
– Up to 8 Chip Selects, each reserved to one of the eight Memory Areas
– Optimized pin multiplexing to reduce latencies on External Memories
• Configurable Chip Select Assignment:
– Burst Flash Controller or Static Memory Controller on NCS0
– SDRAM Controller or Static Memory Controller on NCS1
– Static Memory Controller on NCS3, Optional NAND Flash/SmartMedia Support
– Static Memory Controller on NCS4 - NCS6, Optional CompactFlash Support
– Static Memory Controller on NCS7
3.8
Static Memory Controller
• External memory mapping, 512-Mbyte address space
• Up to 8 Chip Select Lines
• 8- or 16-bit Data Bus
• Remap of Boot Memory
• Multiple Access Modes supported
– Byte Write or Byte Select Lines
6
AT91RM9200
1768E–ATARM–30-Sep-05