Datasheet

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1745FS–ATARM–18-Apr-06
AT91M55800A Summary
PIO Controllers called PIOA and PIOB. The PIO controller enables the generation of an inter-
rupt on input change and insertion of a simple input glitch filter on any of the PIO pins.
8.1.5 WD: Watchdog
The Watchdog is built around a 16-bit counter, and is used to prevent system lock-up if the
software becomes trapped in a deadlock. It can generate an internal reset or interrupt, or
assert an active level on the dedicated pin NWDOVF. All programming registers are pass-
word-protected to prevent unintentional programming.
8.1.6 SF: Special Function
The AT91M55800A provides registers which implement the following special functions.
• Chip identification
• RESET status