The book is the second part and logical continuation of the author's edition "1000 and one microcontroller circuit. Issue 1," published in 2010. The book presents a collection of more than 1000 electrical circuits for the use of microcontrollers in amateur practice. The subsystem of digital output of signals (connection of light, sound, mechanical and other actuating devices) is covered in detail, as well as the circuitry of combined input output units and interfacing devices with computers via RS-232, LPT, PS2, USB, Ethernet interfaces.