SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 432

• 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

432
432
SAM9G35
SAM9G35
After initialization, the DDR2-SDRAM devices are fully functional.
19. A mode Normal command is provided. Program the Normal mode into Mode Register
20. Perform a write access to any DDR2-SDRAM address.
21. Write the refresh rate into the count field in the Refresh Timer register (see
(see
address to acknowledge this command.
(Refresh rate = delay between refresh cycles). The DDR2-SDRAM device requires a
refresh every 15.625 μs or 7.81 μs. With a 133 MHz frequency, the refresh timer count
register must to be set with (15.625*133 MHz) = 2079 i.e. 0x081f or (7.81*133 MHz) =
1039 i.e. 0x040f.
Section 30.7.1 on page
456). Perform a write access to any DDR2-SDRAM
11053B–ATARM–22-Sep-11
11053B–ATARM–22-Sep-11
page
457).