This is a vintage technical reference devoted to programming and hardware interfacing for the Zilog Z-80 microprocessor, one of the major 8-bit processors of the early personal-computer era. Book 2 concentrates especially on connecting digital circuits and peripheral hardware to the Z-80 CPU, including the Z-80 PIO (Parallel Input/Output) and CTC (Counter/Timer Circuit) chips. Contemporary descriptions specifically identify Book 2 as the interfacing volume of the series.

The text covers subjects such as input/output instructions, CPU timing and read/write cycles, interfacing techniques, interrupts, peripheral control, and practical programming routines. Numerous technical diagrams, timing charts, instruction tables, and programming examples are included. It is particularly interesting today as a period reference for retro computing, vintage electronics, Z80 development, computer engineering, and early microprocessor technology.