RESET: ldi r16, 0x01 out DDRB, r16 ; PB0 as output
Unfortunately, a comprehensive modern guide for is difficult to find because the software is over 15 years old (released around 2008–2010). Atmel (now Microchip) discontinued it around 2012, replacing it with AVR Studio 5, 6, 7, and finally Microchip Studio (the modern IDE). avr studio 4.19
Would you like help converting an AVR Studio 4 project to a modern toolchain? RESET: ldi r16, 0x01 out DDRB, r16 ;