Overview

Features

• Advanced RISC Architecture
• Up to 16 MIPS Throughput at 16 MHz
• 16K Bytes of In-System Self-Programmable Flash
• 512 Bytes EEPROM
• 1K Byte Internal SRAM
• 32 Programmable I/O Lines
• In-System Programming by On-chip Boot Program
• 8-channel, 10-bit ADC
• Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes
• One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture
• Four PWM Channels
• Programmable Serial USART
• Master/Slave SPI Serial Interface
• Byte-oriented Two-wire Serial Interface
• Programmable Watchdog Timer with Separate On-chip Oscillator
• External and Internal Interrupt Sources

Pin Configuration

Pin Description

VCC: Digital supply voltage. (+5V)

GND: Ground. (0 V) Note there are 2 ground Pins.

Port A (PA7 - PA0)

Port A serves as the analog inputs to the A/D Converter. Port A also serves as an 8-bit bi-directional I/O port, if the A/D Converter is not used. When pins PA0 to PA7 are used as inputs and are externally pulled low, they will source current if the internal pull-up resistors are activated. The Port A pins are tri-stated when a reset condition becomes active, even if the clock is not running.

Port B (PB7 - PB0)

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). Port B also serves the functions of various special features of the ATmega16 as listed on page 58 of datasheet.

Port C (PC7 - PC0)

Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). Port C also serves the functions of the JTAG interface and other special features of the ATmega16 as listed on page 61 of datasheet. If the JTAG interface is enabled, the pull-up resistors on pins PC5 (TDI), PC3 (TMS) and PC2 (TCK) will be activated even if a reset occurs.

Port D (PD7 - PD0)

Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). Port D also serves the functions of various special features of the ATmega16 as listed on page 63 of datasheet.

RESET: Reset Input. A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running.

XTAL1: External oscillator pin 1

XTAL2: External oscillator pin 2

AVCC: AVCC is the supply voltage pin for Port A and the A/D Converter. It should be externally connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to VCC through a low-pass filter.

AREF: AREF is the analog reference pin for the A/D Converter.

Block Diagram