SAM9XE512 Atmel Corporation, SAM9XE512 Datasheet - Page 323

• Manufacturer Part Number: SAM9XE512
• Manufacturer: Atmel Corporation

Specifications of SAM9XE512

• Flash (kbytes): 512 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 180 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): 2
• Uart: 6
• 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): 312
• 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): 1.65 to 1.95
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

28.7
6254C–ATARM–22-Jan-10
Programming Sequence
Moreover, like the PCK, a status bitin PMC_SR indicates that the Programmable Clock is actu-
ally what has been programmed in the Programmable Clock registers.
As the Programmable Clock Controller does not manage with glitch prevention when switching
clocks, it is strongly recommended to disable the Programmable Clock before any configuration
change and to re-enable it after the change is actually performed.
1. Enabling the Main Oscillator:
2. Checking the Main Oscillator Frequency (Optional):
3. Setting PLL A and divider A:
The main oscillator is enabled by setting the MOSCEN field in the CKGR_MOR register. In
some cases it may be advantageous to define a start-up time. This can be achieved by writ-
ing a value in the OSCOUNT field in the CKGR_MOR register.
Once this register has been correctly configured, the user must wait for MOSCS field in the
PMC_SR register to be set. This can be done either by polling the status register or by wait-
ing the interrupt line to be raised if the associated interrupt to MOSCS has been enabled in
the PMC_IER register.
Code Example:
Start Up Time = 8 * OSCOUNT / SLCK = 56 Slow Clock Cycles.
So, the main oscillator will be enabled (MOSCS bit set) after 56 Slow Clock Cycles.
In some situations the user may need an accurate measure of the main oscillator frequency.
This measure can be accomplished via the CKGR_MCFR register.
Once the MAINRDY field is set in CKGR_MCFR register, the user may read the MAINF field
in CKGR_MCFR register. This provides the number of main clock cycles within sixteen slow
clock cycles.
All parameters necessary to configure PLL A and divider A are located in the CKGR_PLLAR
register. ICPPLLA in PMC_PLLICPR register must be set to 1 before configuring the
CKGR_PLLAR register.
It is important to note that Bit 29 must always be set to 1 when programming the
CKGR_PLLAR register.
The DIVA field is used to control the divider A itself. The user can program a value between
0 and 255. Divider A output is divider A input divided by DIVA. By default, DIVA parameter is
set to 0 which means that divider A is turned off.
The OUTA field is used to select the PLL A output frequency range.
The MULA field is the PLL A multiplier factor. This parameter can be programmed between
0 and 2047. If MULA is set to 0, PLL A will be turned off. Otherwise PLL A output frequency
is PLL A input frequency multiplied by (MULA + 1).
The PLLACOUNT field specifies the number of slow clock cycles before LOCKA bit is set in
the PMC_SR register after CKGR_PLLAR register has been written.
Once CKGR_PLLAR register has been written, the user is obliged to wait for the LOCKA bit
to be set in the PMC_SR register. This can be done either by polling the status register or by
write_register(CKGR_MOR,0x00000701)
AT91SAM9XE128/256/512 Preliminary
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