SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 450

• Manufacturer Part Number: SAM9G20
• Manufacturer: Atmel Corporation

Specifications of SAM9G20

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 400 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: 7
• 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): 95
• 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): 0.9 to 1.1
• Fpu: No
• Mpu / Mmu: No/Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

30.5.6
450
450
SAM9G35
SAM9G35
Write Protected Registers
To prevent any single software error that may corrupt DDRSDRC behavior, the registers listed
below can be write-protected by setting the WPEN bit in the DDRSDRC Write Protect Mode
Register (DDRSDRC_WPMR).
If a write access in a write-protected register is detected, then the WPVS flag in the DDRSDRC
Write Protect Status Register (DDRSDRC_WPSR) is set and the field WPVSRC indicates in
which register the write access has been attempted.
The WPVS flag is automatically reset after reading the DDRSDRC Write Protect Status Register
(DDRSDRC_WPSR).
Following is a list of the write protected registers:
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•
•
•
•
•
•
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“DDRSDRC Mode Register” on page 456
“DDRSDRC Refresh Timer Register” on page 457
“DDRSDRC Configuration Register” on page 458
“DDRSDRC Timing Parameter 0 Register” on page 461
“DDRSDRC Timing Parameter 1 Register” on page 463
“DDRSDRC Timing Parameter 2 Register” on page 464
“DDRSDRC Memory Device Register” on page 467
“DDRSDRC High Speed Register” on page 469
11053B–ATARM–22-Sep-11
11053B–ATARM–22-Sep-11