ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 253

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 16-6. Watchdog Reset
16.3.5
16.3.6
6430D–ATARM–25-Mar-11
WDRPROC = 0
Reset State Priorities
Reset Controller Status Register
Only if
periph_nreset
proc_nreset
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:
(nrst_out)
• General Reset
• Backup Reset
• Watchdog Reset
• Software Reset
• User Reset
• When in User Reset:
• When in Software Reset:
• When in Watchdog Reset:
• RSTTYP field: This field gives the type of the last reset, as explained in previous sections.
RSTTYP
wd_fault
NRST
SLCK
MCK
– 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.
Freq.
Any
Any
Processor Startup
= 2 cycles
XXX
EXTERNAL RESET LENGTH
8 cycles (ERSTL=2)
0x2 = Watchdog Reset
SAM3U Series
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