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
