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4501 Group User’s Manual
Table of contents
2.1 I/O pins .................................................................................................................................... 2-2
2.1.1 I/O ports .......................................................................................................................... 2-2
2.1.2 Related registers ............................................................................................................ 2-5
2.1.4 Notes on use ................................................................................................................ 2-10
2.2 Interrupts ............................................................................................................................... 2-12
2.2.1 Interrupt functions ........................................................................................................ 2-12
2.2.2 Related registers .......................................................................................................... 2-13
2.2.4 Notes on use ................................................................................................................ 2-20
2.3.2 Related registers .......................................................................................................... 2-22
2.3.4 Notes on use ................................................................................................................ 2-32
2.4 A-D converter ....................................................................................................................... 2-33
2.4.1 Related registers .......................................................................................................... 2-34
2.4.3 Notes on use ................................................................................................................ 2-36
2.5.1 Reset circuit .................................................................................................................. 2-38
2.5.3 Notes on use ................................................................................................................ 2-40
2.7 RAM back-up ........................................................................................................................ 2-42
2.7.1 RAM back-up mode ..................................................................................................... 2-42
2.7.2 Related registers .......................................................................................................... 2-44
2.7.3 Notes on use ................................................................................................................ 2-48
2.8.3 Notes on use ................................................................................................................ 2-52