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4502 Group User’s Manual
2.1 I/O pins .................................................................................................................................... 2-2
 2.1.1 I/O ports .......................................................................................................................... 2-2
 2.1.2 Related registers ............................................................................................................ 2-6
 2.1.4 Notes on use ................................................................................................................ 2-11
 2.2.1 Interrupt functions ........................................................................................................ 2-13
 2.2.2 Related registers .......................................................................................................... 2-14
 2.2.4 Notes on use ................................................................................................................ 2-21
 2.3 Timers .................................................................................................................................... 2-22
 2.3.1 Timer functions ............................................................................................................. 2-22
 2.3.2 Related registers .......................................................................................................... 2-23
 2.3.4 Notes on use ................................................................................................................ 2-33
 2.4.1 Related registers .......................................................................................................... 2-35
 2.5.1 Reset circuit .................................................................................................................. 2-39
 2.5.3 Notes on use ................................................................................................................ 2-41
 2.7 RAM back-up ........................................................................................................................ 2-43
 2.7.2 Related registers .......................................................................................................... 2-45
 2.7.3 Notes on use ................................................................................................................ 2-49
 2.8 Oscillation circuit ................................................................................................................ 2-50
 2.8.3 Notes on use ................................................................................................................ 2-53
 Table of contents