ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 473

• 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

28.13 Write Protection Registers
6430D–ATARM–25-Mar-11
To prevent any single software error that may corrupt PMC behavior, certain address spaces
can be write-protected by setting the WPEN bit in the
(PMC_WPMR).
If a write access to the protected registers is detected, then the WPVS flag in the PMC Write
Protect Status Register (US_WPSR) is set and the field WPVSRC indicates in which register the
write access has been attempted.
The WPVS flag is reset by writing the PMC Write Protect Mode Register (PMC_WPMR) with the
appropriate access key, WPKEY.
The protected registers are:
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“PMC System Clock Enable Register” on page 475
“PMC System Clock Disable Register” on page 476
“PMC Peripheral Clock Enable Register” on page 477
“PMC Peripheral Clock Disable Register” on page 478
“PMC UTMI Clock Configuration Register” on page 480
“PMC Clock Generator Main Oscillator Register” on page 481
“PMC Clock Generator PLLA Register” on page 484
“PMC Programmable Clock Register” on page 486
“PMC Fast Startup Mode Register” on page 492
“PMC Fast Startup Polarity Register” on page 493
“PMC Write Protect Mode Register”
SAM3U Series
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