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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