551
11100B–ATARM–31-Jul-12
SAM4S Series [Preliminary]
29.5.14
Write Protection Registers
To prevent any single software error that may corrupt PIO behavior, certain address spaces can
be write-protected by setting the WPEN bit in the
“PIO Write Protect Mode Register”
(PIO_WPMR).
If a write access to the protected registers is detected, then the WPVS flag in the PIO Write Pro-
tect Status Register (PIO_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 PIO Write Protect Mode Register (PIO_WPMR) with the
appropriate access key, WPKEY.
The protected registers are:
•
“PIO Enable Register” on page 556
•
“PIO Disable Register” on page 556
•
“PIO Output Enable Register” on page 557
•
“PIO Output Disable Register” on page 558
•
“PIO Input Filter Enable Register” on page 559
•
“PIO Input Filter Disable Register” on page 559
•
“PIO Multi-driver Enable Register” on page 564
•
“PIO Multi-driver Disable Register” on page 565
•
“PIO Pull Up Disable Register” on page 566
•
“PIO Pull Up Enable Register” on page 566
•
“PIO Peripheral ABCD Select Register 1” on page 568
•
“PIO Peripheral ABCD Select Register 2” on page 569
•
“PIO Output Write Enable Register” on page 574
•
“PIO Output Write Disable Register” on page 574
•
“PIO Pad Pull Down Disable Register” on page 572
•
“PIO Pad Pull Down Status Register” on page 573
•
Содержание SAM4S Series
Страница 44: ...44 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 412: ...412 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1105: ...1105 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1142: ...1142 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 3 100 ball VFBGA Package Drawing ...
Страница 1143: ...1143 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 4 64 lead LQFP Package Drawing ...
Страница 1145: ...1145 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 5 64 lead QFN Package Drawing ...