SAM9261 Atmel Corporation, SAM9261 Datasheet - Page 46

• Manufacturer Part Number: SAM9261
• Manufacturer: Atmel Corporation

Specifications of SAM9261

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 240 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): 1
• Uart: 4
• Ssc: 3
• Sd / Emmc: 1
• Graphic Lcd: Yes
• Video Decoder: No
• Camera Interface: No
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 160
• 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): 1.08 to 1.32
• Fpu: No
• Mpu / Mmu: No/Yes
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Programmer’s Model
2.3
2.3.1
2.3.2
2-4
Memory formats
Big-endian format
Little-endian format
The ARM9E-S views memory as a linear collection of bytes numbered in ascending
order from zero. Bytes 0 to 3 hold the first stored word, and bytes 4 to 7 hold the second
stored word, for example.
The ARM9E-S can treat words in memory as being stored in either:
•
•
In big-endian format, the ARM9E-S stores the most significant byte of a word at the
lowest-numbered byte, and the least significant byte at the highest-numbered byte.
Therefore, byte 0 of the memory system connects to data lines 31 to 24. This is shown
in Figure 2-1.
In little-endian format, the lowest-numbered byte in a word is the least-significant byte
of the word and the highest-numbered byte is the most significant. Therefore, byte 0 of
the memory system connects to data lines 7 to 0. This is shown in Figure 2-2 on
page 2-5.
Big-endian format
Little-endian format.
Copyright © 2000 ARM Limited. All rights reserved.
Higher address
Lower address
Bit
31
• Most significant byte is at lowest address
• Word is addressed by byte address of most significant byte
8
4
0
Figure 2-1 Big-endian addresses of bytes within words
24
23
9
5
1
16
15
10
6
2
8
11
7
7
3
0
ARM DDI 0165B
Word address
8
4
0