SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 62

• Manufacturer Part Number: SAM7SE256
• Manufacturer: Atmel Corporation

Specifications of SAM7SE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 48 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 88
• Ext Interrupts: 88
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• 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): 3.0 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: No

13.2.5
13.2.6
62
SAM7SE512/256/32
Reset State Priorities
Reset Controller Status Register
Figure 13-8. Watchdog Reset
The Reset State Manager manages the following priorities between the different reset sources,
given in descending order:
Particular cases are listed below:
The Reset Controller status register (RSTC_SR) provides several status fields:
WDRPROC = 0
• Power-up Reset
• Brownout Reset
• Watchdog Reset
• Software Reset
• User Reset
• When in User Reset:
• When in Software Reset:
• When in Watchdog Reset:
Only if
– A watchdog event is impossible because the Watchdog Timer is being reset by the
– A software reset is impossible, since the processor reset is being activated.
– A watchdog event has priority over the current state.
– The NRST has no effect.
– The processor reset is active and so a Software Reset cannot be programmed.
– A User Reset cannot be entered.
proc_nreset signal.
periph_nreset
proc_nreset
(nrst_out)
RSTTYP
wd_fault
NRST
SLCK
MCK
Freq.
Any
Any
Processor Startup
= 3 cycles
XXX
EXTERNAL RESET LENGTH
8 cycles (ERSTL=2)
0x2 = Watchdog Reset
6222F–ATARM–14-Jan-11