SAM9261 Atmel Corporation, SAM9261 Datasheet - Page 236

• 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

24.3.1
24.3.2
24.3.3
236
AT91SAM9261
Main Oscillator Connections
Main Oscillator Startup Time
Main Oscillator Control
Figure 24-2. Main Oscillator Block Diagram
The Clock Generator integrates a Main Oscillator that is designed for a
crystal. The typical crystal connection is illustrated in
required for crystals with frequencies lower than 8 MHz. For further details on the electrical char-
acteristics of the Main Oscillator, see the section “DC Characteristics” of the product datasheet.
Figure 24-3. Typical Crystal Connection
The startup time of the Main Oscillator is given in the DC Characteristics section of the product
datasheet. The startup time depends on the crystal frequency and decreases when the fre-
quency rises.
To minimize the power required to start up the system, the main oscillator is disabled after reset
and slow clock is selected.
The software enables or disables the main oscillator so as to reduce power consumption by
clearing the MOSCEN bit in the Main Oscillator Register (CKGR_MOR).
Slow Clock
XOUT
SLCK
XIN
XIN
AT91 Microcontroller
Main Clock
Frequency
OSCOUNT
Oscillator
MOSCEN
Oscillator
XOUT
Counter
Counter
Main
Main
1K
Figure
GND
24-3. The 1 k
Main Clock
MAINCK
MAINRDY
MOSCS
MAINF
3 to 20
6062N–ATARM–3-Oct-11
Ω
MHz fundamental
resistor is only