SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 201

• 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

22. SDRAM Controller (SDRAMC)
22.1
22.2
6384E–ATARM–05-Feb-10
Overview
I/O Lines Description
The SDRAM Controller (SDRAMC) extends the memory capabilities of a chip by providing the
interface to an external 16-bit or 32-bit SDRAM device. The page size supports ranges from
2048 to 8192 and the number of columns from 256 to 2048. It supports byte (8-bit), half-word
(16-bit) and word (32-bit) accesses.
The SDRAM Controller supports a read or write burst length of one location. It keeps track of the
active row in each bank, thus maximizing SDRAM performance, e.g., the application may be
placed in one bank and data in the other banks. So as to optimize performance, it is advisable to
avoid accessing different rows in the same bank.
The SDRAM controller supports a CAS latency of 1, 2 or 3 and optimizes the read access
depending on the frequency.
The different modes available - self-refresh, power-down and deep power-down modes - mini-
mize power consumption on the SDRAM device.
Table 22-1.
Name
SDCK
SDCKE
SDCS
BA[1:0]
RAS
CAS
SDWE
NBS[3:0]
SDRAMC_A[12:0]
D[31:0]
I/O Line Description
Description
SDRAM Clock
SDRAM Clock Enable
SDRAM Controller Chip Select
Bank Select Signals
Row Signal
Column Signal
SDRAM Write Enable
Data Mask Enable Signals
Address Bus
Data Bus
Output
Output
Output
Output
Output
Output
Output
Output
Output
Type
AT91SAM9G20
I/O
Active Level
High
Low
Low
Low
Low
Low
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