I/O: Really, the core function of a microcontroller is Input/Output. In fact, out of the ATmega32's 40 pins, 32 pins are set aside for I/O. They are organized into four 8-pin ports named PORTA, PORTB, PORTC, and PORTD. The STK 200 makes it really easy to access these ports by giving them each headers. The board even labels the headers using the standard naming convention established by the AVR family (PORTA, etc.). Each header includes it's own VCC and GND, which devices almost always require. LEDs and switches are probably the most common form of I/O; conveniently, the STK 200 has 8 LEDs and 8 switches built into the board. You can dedicate ports to the LEDs, the switches or both using a 10-pin ribbon cable provided with the board and pictured below. PORTB is lined up with the LED input header and PORTD is lined up with the switches output header for an easy connection.
|STK 200: I/O|