Manual

i
AT90S/LS4433
1042G–AVR–09/02
Table of Contents Features................................................................................................. 1
Pin Configurations................................................................................ 2
Description............................................................................................ 3
Block Diagram ...................................................................................................... 4
Pin Descriptions.................................................................................................... 5
Clock Options ....................................................................................................... 6
Architectural Overview......................................................................... 7
General Purpose Register File ........................................................................... 10
ALU – Arithmetic Logic Unit................................................................................ 11
In-System Programmable Flash Program Memory ............................................ 11
SRAM Data Memory........................................................................................... 11
Program and Data Addressing Modes................................................................ 12
EEPROM Data Memory...................................................................................... 16
Memory Access Times and Instruction Execution Timing .................................. 16
I/O Memory......................................................................................................... 17
Reset and Interrupt Handling.............................................................................. 20
Sleep Modes....................................................................................................... 31
Timer/Counters ................................................................................... 33
Timer/Counter Prescaler..................................................................................... 33
8-bit Timer/Counter0........................................................................................... 33
16-bit Timer/Counter1......................................................................... 35
Watchdog Timer.................................................................................. 43
EEPROM Read/Write Access............................................................. 45
Prevent EEPROM Corruption ............................................................................. 47
Serial Peripheral Interface – SPI........................................................ 48
SS Pin Functionality............................................................................................ 49
Data Modes ........................................................................................................ 50
UART.................................................................................................... 53
Data Transmission.............................................................................................. 53
Data Reception................................................................................................... 54
UART Control ..................................................................................................... 57
Analog Comparator ............................................................................ 62
Analog-to-Digital Converter............................................................... 64
Features.............................................................................................................. 64
Operation ............................................................................................................ 65