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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

(ICFn) must be cleared by software (writing a logical one to the I/O bit location). For

measuring frequency only, the clearing of the ICFn Flag is not required (if an interrupt

handler is used).

Output Compare Units The 16-bit comparator continuously compares TCNTn with the Output Compare Regis-

ter (OCRnx). If TCNT equals OCRnx the comparator signals a match. A match will set

the Output Compare Flag (OCFnx) at the next timer clock cycle

. If enabled (OCIEnx =

1), the Output Compare Flag generates an output compare interrupt. The OCFnx Flag is

automatically cleared when the interrupt is executed. Alternatively the OCFnx Flag can

be cleared by software by writing a logical one to its I/O bit location. The Waveform Gen-

erator uses the match signal to generate an output according to operating mode set by

the Waveform Generation mode (WGMn3:0) bits and Compare Output mode

(COMnx1:0) bits. The TOP and BOTTOM signals are used by the Waveform Generator

for handling the special cases of the extreme values in some modes of operation (See

“Modes of Operation” on page 117.)

A special feature of output compare unit A allows it to define the Timer/Counter TOP

value (i.e., counter resolution). In addition to the counter resolution, the TOP value

defines the period time for waveforms generated by the Waveform Generator.

Figure 49 shows a block diagram of the output compare unit. The small “n” in the regis-

ter and bit names indicates the device number (n = n

for Timer/Counter n), and the “x”

indicates output compare unit (A/B). The elements of the block diagram that are not

directly a part of the output compare unit are gray shaded.

Figure 49. Output Compare Unit, Block Diagram

The OCRnx Register is double buffered when using any of the twelve Pulse Width Mod-

ulation (PWM) modes. For the normal and Clear Timer on Compare (CTC) modes of

operation, the double buffering is disabled. The double buffering synchronizes the

update of the OCRnx Compare Register to either TOP or BOTTOM of the counting

OCFnx (Int.Req.)

(16-bit Comparator )

OCRnx Buffer (16-bit Register)

OCRnxH Buf. (8-bit)

OCnx

TEMP (8-bit)

DATA BUS

(8-bit)

OCRnxL Buf. (8-bit)

TCNTn (16-bit Counter)

TCNTnH (8-bit) TCNTnL (8-bit)

COMnx1:0WGMn3:0

OCRnx (16-bit Register)

OCRnxH (8-bit) OCRnxL (8-bit)

Waveform Generator

TOP

BOTTOM