SAM9G10 Atmel Corporation, SAM9G10 Datasheet - Page 175

• Manufacturer Part Number: SAM9G10
• Manufacturer: Atmel Corporation

Specifications of SAM9G10

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 266 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): 16
• 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

21.4.1
21.4.2
11053B–ATARM–22-Sep-11
Switch from Internal 32 kHz RC Oscillator to the 32,768 Hz Crystal
Bypass the 32768 Hz Oscillator
Figure 21-2. Slow Clock
RCEN, OSC32EN,OSCSEL and OSC32BYP bits are located in the Slow Clock Control Register
(SCKCR) located at address 0xFFFFFE50 in the backed up part of the System Controller and so
are preserved while VDDBU is present.
After a VDDBU power on reset, the default configuration is RCEN = 1, OSC32EN = 0 and OSC-
SEL = 0, BYPASS = 0, allowing the system to start on the internal 32 kHz RC oscillator.
The programmer controls the slow clock switching by software and so must take precautions
during the switching phase.
To switch from internal 32 kHz RC oscillator to the 32,768 Hz crystal, the programmer must exe-
cute the following sequence:
The following step must be added to bypass the 32768 Hz Oscillator.
• Switch the master clock to a source different from slow clock (PLL or Main Oscillator) through
• Enable the 32,768 Hz oscillator by setting the bit OSC32EN to 1.
• Wait 32,768 Hz Startup Time for clock stabilization (software loop).
• Switch from internal 32 kHz RC to 32,768 Hz oscillator by setting the bit OSCSEL to 1.
• Wait 5 slow clock cycles for internal resynchronization.
• Disable the 32 kHz RC oscillator by setting the bit RCEN to 0.
• Switch the master clock back to the slow clock domain
• An external clock must be connected on XIN32.
• Enable the bypass path OSC32BYP bit set to 1.
• Disable the 32768 Hz oscillator by setting the bit OSC32EN to 0.
the Power Management Controller.
XOUT32
XIN32
Clock Generator
Slow Clock
Oscillator
On Chip
RC OSC
RCEN
Slow Clock
SLCK
OSCSEL
OSC32EN
OSC32BYP
SAM9G35
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