SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 91

• 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

14.3.4.2
Figure 14-5. Wake-up State
14.3.4.3
6384E–ATARM–05-Feb-10
backup_nreset
periph_nreset
Wake-up Reset
Main Supply
User Reset
POR output
proc_nreset
(nrst_out)
RSTTYP
SLCK
NRST
MCK
The Wake-up Reset occurs when the Main Supply is down. When the Main Supply POR output
is active, all the reset signals are asserted except backup_nreset. When the Main Supply pow-
ers up, the POR output is resynchronized on Slow Clock. The processor clock is then re-enabled
during 3 Slow Clock cycles, depending on the requirements of the ARM processor.
At the end of this delay, the processor and other reset signals rise. The field RSTTYP in
RSTC_SR is updated to report a Wake-up Reset.
The “nrst_out” remains asserted for EXTERNAL_RESET_LENGTH cycles. As RSTC_MR is
backed-up, the programmed number of cycles is applicable.
When the Main Supply is detected falling, the reset signals are immediately asserted. This tran-
sition is synchronous with the output of the Main Supply POR.
The User Reset is entered when a low level is detected on the NRST pin and the bit URSTEN in
RSTC_MR is at 1. The NRST input signal is resynchronized with SLCK to insure proper behav-
ior of the system.
The User Reset is entered as soon as a low level is detected on NRST. The Processor Reset
and the Peripheral Reset are asserted.
The User Reset is left when NRST rises, after a two-cycle resynchronization time and a 3-cycle
processor startup. The processor clock is re-enabled as soon as NRST is confirmed high.
Resynch.
2 cycles
XXX
Processor Startup
EXTERNAL RESET LENGTH
= 3 cycles
= 4 cycles (ERSTL = 1)
0x1 = WakeUp Reset
AT91SAM9G20
Freq.
Any
XXX
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