SAM9XE256 Atmel Corporation, SAM9XE256 Datasheet - Page 223

• Manufacturer Part Number: SAM9XE256
• Manufacturer: Atmel Corporation

Specifications of SAM9XE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 180 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 3
• Usb Speed: Full Speed
• Usb Interface: Host, Device
• Spi: 2
• Twi (i2c): 2
• Uart: 6
• Ssc: 1
• Ethernet: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: Yes
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 312
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.65 to 1.95
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

ARM DDI0198D
MMU
Figure B-10 shows the flow and precedence of CP15 c15 control bits in resolving the
cachable and bufferable attributes of a memory reference.
M, C, and I bits
Copyright © 2001-2003 ARM Limited. All rights reserved.
MDDEB bit:
MMU disabled,
DCache enabled
C and B bits
NCNB
NCB
CNB (write-through)
CB (write-back)
Memory Region Remap Register
Debug Override Register
Page table descriptor
Control Register
remapping
Memory
region
Figure B-10 Memory region attribute resolution
NCNB
NCB
CNB (write-through)
CB (write-back)
CP15 Test and Debug Registers
Force NCB store
to be NCNB
FNCB bit:
NCB store
NCNB
Force
to be
B-17