AT89C51ID2-RDTIM datasheet(157/159 Pages) ATMEL

157 / 159 page

157

AT89C51ID2

4289A–8051–09/03

Pulse Width Modulator Mode.............................................................................. 51

PCA Watchdog Timer ......................................................................................... 52

Serial I/O Port ...................................................................................... 53

Framing Error Detection ..................................................................................... 53

Automatic Address Recognition.......................................................................... 54

Registers............................................................................................................. 56

Baud Rate Selection for UART for Mode 1 and 3............................................... 56

UART Registers.................................................................................................. 59

Interrupt System ................................................................................. 64

Registers............................................................................................................. 65

Interrupt Sources and Vector Addresses............................................................ 72

Power Management ............................................................................ 73

Introduction ......................................................................................................... 73

Idle Mode ............................................................................................................ 73

Power-Down Mode ............................................................................................. 73

Registers............................................................................................................. 76

Keyboard Interface ............................................................................. 77

Registers............................................................................................................. 78

2-wire Interface (TWI) ......................................................................... 81

Description.......................................................................................................... 83

Notes .................................................................................................................. 86

Registers............................................................................................................. 96

Serial Port Interface (SPI)................................................................... 99

Features.............................................................................................................. 99

Signal Description............................................................................................... 99

Functional Description ...................................................................................... 101

Hardware Watchdog Timer .............................................................. 108

Using the WDT ................................................................................................. 108

WDT During Power Down and Idle................................................................... 109

ONCE(TM) Mode (ON Chip Emulation) ........................................... 110

Power-off Flag................................................................................... 111

EEPROM Data Memory..................................................................... 112

Write Data......................................................................................................... 112

Read Data......................................................................................................... 114

Registers........................................................................................................... 115

AT89C51ID2-RDTIM Datasheet(PDF) 157 Page - ATMEL Corporation