Manual
Table Of Contents
- Features
- Pin Configurations
- Description
- Architectural Overview
- General Purpose Register File
- ALU – Arithmetic Logic Unit
- In-System Programmable Flash Program Memory
- SRAM Data Memory
- Program and Data Addressing Modes
- Register Direct, Single Register Rd
- Register Direct, Two Registers Rd and Rr
- I/O Direct
- Data Direct
- Data Indirect with Displacement
- Data Indirect
- Data Indirect with Pre- decrement
- Data Indirect with Post- increment
- Constant Addressing Using the LPM Instruction
- Indirect Program Addressing, IJMP and ICALL
- Relative Program Addressing, RJMP and RCALL
- EEPROM Data Memory
- Memory Access Times and Instruction Execution Timing
- I/O Memory
- Reset and Interrupt Handling
- Reset Sources
- Power-on Reset
- External Reset
- Brown-out Detection
- Watchdog Reset
- MCU Status Register – MCUSR
- Interrupt Handling
- General Interrupt Mask Register – GIMSK
- General Interrupt Flag Register – GIFR
- Timer/Counter Interrupt Mask Register – TIMSK
- Timer/Counter Interrupt Flag Register – TIFR
- External Interrupts
- Interrupt Response Time
- MCU Control Register – MCUCR
- Sleep Modes
- Timer/Counters
- 16-bit Timer/Counter1
- Watchdog Timer
- EEPROM Read/Write Access
- Serial Peripheral Interface – SPI
- UART
- Analog Comparator
- Analog-to-Digital Converter
- I/O Ports
- Memory Programming
- Electrical Characteristics
- External Clock Drive Waveforms
- Typical Characteristics
- Register Summary
- Instruction Set Summary
- Ordering Information
- Packaging Information
- Errata for AT90S/LS4433 Rev. Rev. C/D/E/F
- Data Sheet ChangeLog for AT90S/LS4433
- Table of Contents
22
AT90S/LS4433
1042G–AVR–09/02
Figure 24. Reset Logic
Note: 1. The Power-on Reset will not work unless the supply voltage has been below V
POT
(falling).
Table 4. Reset Characteristics (V
CC
=5.0V)
Symbol Parameter Min Typ Max Units
V
POT
(1)
Power-on Reset
Threshold
Voltage, rising
1.0 1.4 1.8 V
Power-on Reset
Threshold
Voltage, falling
0.4 0.6 0.8 V
V
RST
RESET Pin
Threshold
Voltage
0.6 V
CC
V
V
BOT
Brown-out Reset
Threshold
Voltage
2.2
(BODLEVEL=1)
2.7
(BODLEVEL=1)
3.0
(BODLEVEL=1)
V
3.5
(BODLEVEL=0)
4.0
(BODLEVEL=0)
4.5
(BODLEVEL=0)
MCU Status
Register (MCUSR)
Brown-out
Reset Circuit
Power-on Reset
Circuit
BODEN
BODLEVEL
Delay Counters
CKSEL[2:0]
CK
Full
WDRF
BORF
EXTRF
PORF
DATA B US
Reset Circuit
Watchdog
Timer
On-chip
RC Oscillator
Counter Reset
Internal Reset
RESET
V
CC