SAM3U2E Atmel Corporation, SAM3U2E Datasheet - Page 248

• Manufacturer Part Number: SAM3U2E
• Manufacturer: Atmel Corporation

Specifications of SAM3U2E

• Flash (kbytes): 128 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 96 MHz
• Cpu: Cortex-M3
• # Of Touch Channels: 57
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 1
• Quadrature Decoder Channels: 1
• Usb Speed: Hi-Speed
• Usb Interface: Device
• Spi: 5
• Twi (i2c): 2
• Uart: 5
• Ssc: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 12
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 36
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: No
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.62 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

16.3.4.2
16.3.4.3
Figure 16-4. User Reset State
248
periph_nreset
proc_nreset
(nrst_out)
RSTTYP
SAM3U Series
NRST
SLCK
NRST
MCK
Backup Reset
User Reset
A Backup reset occurs when the chip returns from Backup mode. The vddcore_nreset signal is
asserted by the Supply Controller when a Backup reset occurs.
The field RSTTYP in RSTC_SR is updated to report a Backup Reset.
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.
When the processor reset signal is released, the RSTTYP field of the Status Register
(RSTC_SR) is loaded with the value 0x4, indicating a User Reset.
T h e
EXTERNAL_RESET_LENGTH Slow Clock cycles, as programmed in the field ERSTL. How-
ever, if NRST does not rise after EXTERNAL_RESET_LENGTH because it is driven low
externally, the internal reset lines remain asserted until NRST actually rises.
Resynch.
2 cycles
Any
Freq.
Any
N R S T
>= EXTERNAL RESET LENGTH
M a n a g e r
g u a r a n t e e s
Resynch.
2 cycles
XXX
t h a t
Processor Startup
t h e
= 2 cycles
N R S T
l i n e
0x4 = User Reset
i s
6430E–ATARM–29-Aug-11
a s s e r t e d
f o r