The Acorn Businesss Computer was produced in 1984 by Acorn Computers in the UK. The ABC-110 was a CP/M 2.2 computer running on a Z80 processor with a 6502 processor for I/O functions. The c omputer came with a color monitor, a 10MByte Hard Disk Drive, and a 720kByte 5.25" Floppy Disk Drive. The machine was equipped with 64kByte of RAM.

The ABC 110 was the fourth in a series of eight ABC computers:

• ABC Personal Assistant

  6502 CPU @ 2MHz, 64kB RAM, 640kB FDD

• ABC Terminal

  6502 CPU @ 2MHz, 64kB RAM, No disk, VT100 terminal emulator in ROM

• ABC 100

  Z80 CPU, 6502 I/O CPU, 64kB RAM, dual 720k 5.25" FDD, CP/M 2.2

• ABC 110

  Z80 CPU, 6502 I/O CPU, 64kB RAM, 720k 5.25" FDD, 10 MB HDD, CP/M 2.2

• ABC 200

  32016 CPU, 6502 I/O CPU, 512kB RAM, Dual 720k 5.25" FDD, Xenix

• ABC 210

  32016 CPU, 6502 I/O CPU, 1MB RAM, 720k 5.25" FDD, 10MB HDD, Xenix

• ABC 300

  80286 CPU, 6502 I/O CPU, 1MB RAM, Dual 720k 5.25" FDD, DOS 286+GEM

• ABC 310

  80286 CPU, 6502 I/O CPU, 1MB RAM, 720k 5.25" FDD, 10MB HDD, DOS 286+GEM

The Z80 quickly became popular in the personal computer market, with many early personal computers, such as the TRS-80 and Sinclair ZX80, using the Z80 as their central processing unit (CPU). It was also widely used in home computers, such as the MSX range, SORD, and the Amstrad CPC, as well as in many arcade games. Additionally, it was also used in other applications such as industrial control systems, and embedded systems. The Z80 was widely used until the mid-1980s, when it was gradually replaced by newer microprocessors such as the Intel 80286 and the Motorola 68000.

The Z80 microprocessor was developed by Zilog, a company founded by Federico Faggin in 1974. The Z80 was released in July 1976, as a successor to the Intel 8080. It was designed to be fully compatible with the 8080, but also included new features such as an improved instruction set, more powerful interrupts, and a more sophisticated memory management system.

Originally the Z80 was intended for use in embedded systems, just as the 8080 CPU. But the combination of compatibility, superior performance to other CPUs of the era, and the affordability led to a widespread use in arcade video game systems, and later in home computers such as the Osborne 1, TRS-80, ColecoVision, ZX Spectrum, MSX, Sega's Master System and many more. The Z-80 ran the original Pac-Man arcade cabinet. The Z-80 was used even in the Game Gear (1990s), and the TI-81 and succeeding graphic calculators.

The Z-80 remained in production until June of 2024, 48 years after its original release. Zilog replaced the processor with its successor the eZ80, an 8-bit microprocessor that features expanded memory addressing up to 16 megabytes, and running up to 50MHz, comparable to a Z80 clocked at 150MHz.

The 6502 CPU in the ABC x10 series was only used for I/O functions. The central CPU was the Z80 which ran the operating system CP/M. The 6502 was used in many of the ABC computers to control the floppy disk, hard drive and other peripherals.

The 6502 is an 8-bit MicroProcessor designed by MOS Technology. The team was led by Chuck Peddle and had also worked on the Motorola 6800. The 6502 is a simplified, but faster and cheaper design than the 6800.

The 6502 was introduced in 1975 and was the cheapest microprocessor on the market. Together with the Zilog Z80, the 6502 helped start the home computer revolution of the 1980s. The 6502 was used in a wide range of devices: the Atari 2600, the 8-bit Atari home computers, the Apple II, the Nintendo Entertainment System, the Commodore 64, the BBC Micro and many others. All used the 6502 or a variation of it.

The 6502 is a 1MHz design, while the 6502A is designed for 2MHz. The 6502A is 100% compatible with the original 6502.

Commodore soon bought MOS Technology, but conitnued to sell the microprocessor to competitors and licensed the design to other manufacturers.