4551 Group User’s Manual
ii
2.1 I/O pins .................................................................................................................................... 2-2
2.1.1 I/O ports .......................................................................................................................... 2-2
2.1.2 Related registers ............................................................................................................ 2-4
2.1.4 Notes on use .................................................................................................................. 2-8
2.2 Interrupts ................................................................................................................................. 2-9
2.2.1 Interrupt functions .......................................................................................................... 2-9
2.2.2 Related registers .......................................................................................................... 2-10
2.2.4 Notes on use ................................................................................................................ 2-16
2.3 Timers .................................................................................................................................... 2-17
2.3.2 Related registers .......................................................................................................... 2-17
2.3.4 Notes on use ................................................................................................................ 2-24
2.4.2 Related registers .......................................................................................................... 2-26
2.4.4 Notes on use ................................................................................................................ 2-32
2.5.2 Related registers .......................................................................................................... 2-34
2.5.4 Notes on use ................................................................................................................ 2-38
2.6 Power down function .......................................................................................................... 2-39
2.6.2 Power down function ................................................................................................... 2-41
2.6.3 Related register ............................................................................................................ 2-44
2.6.5 Notes on use ................................................................................................................ 2-45
2.8 Oscillation circuit ................................................................................................................ 2-50
2.8.1 Oscillation circuit .......................................................................................................... 2-50
2.8.3 Notes on use ................................................................................................................ 2-51
Table of contents