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Table Of Contents

Features
Pin Configurations
- Disclaimer
Overview
- Block Diagram
- ATmega161 and ATmega162 Compatibility
  - ATmega161 Compatibility Mode
- Pin Descriptions
- About Code Examples
AVR CPU Core
- Introduction
- Architectural Overview
- ALU – Arithmetic Logic Unit
- Status Register
- General Purpose Register File
  - The X-register, Y-register, and Z-register
- Stack Pointer
- Instruction Execution Timing
- Reset and Interrupt Handling
  - Interrupt Response Time
AVR ATmega162 Memories
- In-System Reprogrammable Flash Program Memory
- SRAM Data Memory
  - Data Memory Access Times
- EEPROM Data Memory
- I/O Memory
- External Memory Interface
- XMEM Register Description
System Clock and Clock Options
- Clock Systems and their Distribution
- Clock Sources
- Default Clock Source
- Crystal Oscillator
- Low-frequency Crystal Oscillator
- Calibrated Internal RC Oscillator
  - Oscillator Calibration Register – OSCCAL
- External Clock
- Clock output buffer
- Timer/Counter Oscillator
- System Clock Prescaler
  - Clock Prescale Register – CLKPR
Power Management and Sleep Modes
- MCU Control Register – MCUCR
- MCU Control and Status Register – MCUCSR
- Extended MCU Control Register – EMCUCR
- Idle Mode
- Power-down Mode
- Power-save Mode
- Standby Mode
- Extended Standby Mode
- Minimizing Power Consumption
System Control and Reset
- Resetting the AVR
- Reset Sources
- Power-on Reset
- External Reset
- Brown-out Detection
- Watchdog Reset
- MCU Control and Status Register – MCUCSR
- Internal Voltage Reference
  - Voltage Reference Enable Signals and Start-up Time
- Watchdog Timer
  - Watchdog Timer Control Register – WDTCR
- Timed Sequences for Changing the Configuration of the Watchdog Timer
Interrupts
- Interrupt Vectors in ATmega162
  - Moving Interrupts Between Application and Boot Space
  - General Interrupt Control Register – GICR
I/O-Ports
- Introduction
- Ports as General Digital I/O
- Alternate Port Functions
- Register Description for I/O-Ports
External Interrupts
- MCU Control Register – MCUCR
- Extended MCU Control Register – EMCUCR
- General Interrupt Control Register – GICR
- General Interrupt Flag Register – GIFR
- Pin Change Mask Register 1 – PCMSK1
- Pin Change Mask Register 0 – PCMSK0
8-bit Timer/Counter0 with PWM
- Overview
  - Registers
  - Definitions
- Timer/Counter Clock Sources
- Counter Unit
- Output Compare Unit
- Compare Match Output Unit
  - Compare Output Mode and Waveform Generation
- Modes of Operation
- Timer/Counter Timing Diagrams
- 8-bit Timer/Counter Register Description
Timer/Counter0, Timer/Counter1, and Timer/Counter3 Prescalers
- Internal Clock Source
- Prescaler Reset
- External Clock Source
- Special Function IO Register – SFIOR
16-bit Timer/Counter (Timer/Counter1 and Timer/Counter3)
- Restriction in ATmega161 Compatibility Mode
- Overview
- Accessing 16-bit Registers
  - Reusing the Temporary High Byte Register
- Timer/Counter Clock Sources
- Counter Unit
- Input Capture Unit
- Output Compare Units
- Compare Match Output Unit
  - Compare Output Mode and Waveform Generation
- Modes of Operation
- Timer/Counter Timing Diagrams
- 16-bit Timer/Counter Register Description
8-bit Timer/Counter2 with PWM and Asynchronous operation
- Overview
  - Registers
  - Definitions
- Timer/Counter Clock Sources
- Counter Unit
- Output Compare Unit
- Compare Match Output Unit
  - Compare Output Mode and Waveform Generation
- Modes of Operation
- Timer/Counter Timing Diagrams
- 8-bit Timer/Counter Register Description
- Asynchronous operation of the Timer/Counter
- Timer/Counter Prescaler
  - Special Function IO Register – SFIOR
Serial Peripheral Interface – SPI
- SS Pin Functionality
- Data Modes
USART
- Dual USART
  - AVR USART vs. AVR UART – Compatibility
- Clock Generation
- Frame Formats
  - Parity Bit Calculation
- USART Initialization
- Data Transmission – The USART Transmitter
- Data Reception – The USART Receiver
- Asynchronous Data Reception
- Multi-processor Communication Mode
  - Using MPCM
- Accessing UBRRH/ UCSRC Registers
  - Write Access
  - Read Access
- USART Register Description
- Examples of Baud Rate Setting
Analog Comparator
- Analog Comparator Control and Status Register – ACSR
JTAG Interface and On-chip Debug System
- Features
- Overview
- Test Access Port – TAP
- TAP Controller
- Using the Boundary- scan Chain
- Using the On-chip Debug system
- On-chip debug specific JTAG instructions
- On-chip Debug Related Register in I/O Memory
  - On-chip Debug Register – OCDR
- Using the JTAG Programming Capabilities
- Bibliography
IEEE 1149.1 (JTAG) Boundary-scan
- Features
- System Overview
- Data Registers
- Boundary-scan Specific JTAG Instructions
- Boundary-scan Chain
- ATmega162 Boundary- scan Order
- Boundary-scan Description Language Files
Boot Loader Support – Read-While-Write Self-programming
- Features
- Application and Boot Loader Flash Sections
  - Application Section
  - BLS – Boot Loader Section
- Read-While-Write and No Read-While-Write Flash Sections
  - RWW – Read-While-Write Section
  - NRWW – No Read-While-Write Section
- Boot Loader Lock Bits
- Entering the Boot Loader Program
  - Store Program Memory Control Register – SPMCR
- Addressing the Flash During Self- programming
- Self-programming the Flash
Memory Programming
- Program And Data Memory Lock Bits
- Fuse Bits
  - Latching of Fuses
- Signature Bytes
- Calibration Byte
- Parallel Programming Parameters, Pin Mapping, and Commands
  - Signal Names
- Parallel Programming
- Serial Downloading
- SPI Serial Programming Pin Mapping
- Programming via the JTAG Interface
Electrical Characteristics
- Absolute Maximum Ratings*
- DC Characteristics
- External Clock Drive Waveforms
- External Clock Drive
- SPI Timing Characteristics
- External Data Memory Timing
ATmega162 Typical Characteristics
- Active Supply Current
- Idle Supply Current
- Power-down Supply Current
- Power-save Supply Current
- Standby Supply Current
- Pin Pull-up
- Pin Driver Strength
- Pin Thresholds and Hysteresis
- BOD Thresholds and Analog Comparator Offset
- Internal Oscillator Speed
- Current Consumption of Peripheral Units
- Current Consumption in Reset and Reset Pulsewidth
Register Summary
Instruction Set Summary
Ordering Information
Packaging Information
- 44A
- 40P6
- 44M1
Erratas
- ATmega162, all rev.
Datasheet Change Log for ATmega162
- Changes from Rev. 2513D-04/03 to Rev. 2513E-09/03
- Changes from Rev. 2513C-09/02 to Rev. 2513D-04/03
- Changes from Rev. 2513B-09/02 to Rev. 2513C-09/02
- Changes from Rev. 2513A-05/02 to Rev. 2513B-09/02
Table of Contents

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ATmega162/V

2513E–AVR–09/03

Fast PWM Mode The fast Pulse Width Modulation or fast PWM mode (WGMn3:0 = 5,6,7,14, or 15) pro-

vides a high frequency PWM waveform generation option. The fast PWM differs from

the other PWM options by its single-slope operation. The counter counts from BOTTOM

to TOP then restarts from BOTTOM. In non-inverting Compare Output mode, the Output

Compare (OCnx) is set on the Compare Match between TCNTn and OCRnx, and

cleared at TOP. In inverting Compare Output mode output is cleared on Compare Match

and set at TOP. Due to the single-slope operation, the operating frequency of the fast

PWM mode can be twice as high as the phase correct and phase and frequency correct

PWM modes that use dual-slope operation. This high frequency makes the fast PWM

mode well suited for power regulation, rectification, and DAC applications. High fre-

quency allows physically small sized external components (coils, capacitors), hence

reduces total system cost.

The PWM resolution for fast PWM can be fixed to 8-, 9-, or 10-bit, or defined by either

ICRn or OCRnA. The minimum resolution allowed is 2-bit (ICRn or OCRnA set to

0x0003), and the maximum resolution is 16-bit (ICRn or OCRnA set to MAX). The PWM

resolution in bits can be calculated by using the following equation:

In fast PWM mode the counter is incremented until the counter value matches either

one of the fixed values 0x00FF, 0x01FF, or 0x03FF (WGMn3:0 = 5, 6, or 7), the value in

ICRn (WGMn3:0 = 14), or the value in OCRnA (WGMn3:0 = 15). The counter is then

cleared at the following timer clock cycle. The timing diagram for the fast PWM mode is

shown in Figure 52. The figure shows fast PWM mode when OCRnA or ICRn is used to

define TOP. The TCNTn value is in the timing diagram shown as a histogram for illus-

trating the single-slope operation. The diagram includes non-inverted and inverted PWM

outputs. The small horizontal line marks on the TCNTn slopes represent compare

matches between OCRnx and TCNTn. The OCnx Interrupt Flag will be set when a Com-

pare Match occurs.

Figure 52. Fast PWM Mode, Timing Diagram

The Timer/Counter Overflow Flag (TOVn) is set each time the counter reaches TOP. In

addition the OCnA or ICFn Flag is set at the same timer clock cycle as TOVn is set

when either OCRnA or ICRn is used for defining the TOP value. If one of the interrupts

are enabled, the interrupt handler routine can be used for updating the TOP and com-

pare values.

FPWM

TOP 1+()log

2()log

-----------------------------------=

TCNTn

OCRnx / TOP Update

and TOVn Interrupt Flag

Set and OCnA Interrupt

Flag Set or ICFn

Interrupt Flag Set

(Interrupt on TOP)

1 7

Period

2 3 4 5 6 8

OCnx

(COMnx1:0 = 2)

(COMnx1:0 = 3)