Commodore 128

Definition of Commodore 128

The Commodore 128 (C128) is a personal computer introduced by Commodore International in January 1985. It is an 8-bit computer that serves as an improved successor to the popular Commodore 64, featuring 128 kilobytes of RAM, a faster CPU, and additional hardware features. The C128 supports three operating modes, providing compatibility with its predecessor, as well as offering native C128 and CP/M operating modes for enhanced capabilities.


The phonetics of the keyword “Commodore 128” would be:K – kiloO – oscarM – mikeM – mikeO – oscarD – deltaO – oscarR – romeoE – echo (space)1 – ONE2 – TWO8 – EIGHT

Key Takeaways

  1. The Commodore 128 was a highly popular 8-bit home computer launched in 1985, offering users the ability to operate in multiple modes, including C64, CP/M, and enhanced 128 mode.
  2. A distinguishing feature was its 2MHz processor that allowed faster computing speeds and improved graphics capabilities while retaining backwards compatibility with the bestselling Commodore 64.
  3. It provided users with a friendlier programming environment, having improved BASIC 7.0 and 128 KB of RAM, enabling more complex software and games to be developed.

Importance of Commodore 128

The Commodore 128 (C128) is an important technology term because it represents a milestone in the evolution of personal computing during the 1980s.

As the successor to the highly popular Commodore 64, the C128 aimed to improve upon its predecessor by offering an increased memory capacity of 128KB, a faster CPU (Zilog Z80), and enhanced graphics and sound capabilities, which made it more versatile and powerful.

Additionally, the C128 boasted a unique dual-mode feature, allowing it to run both Commodore 64 and CP/M software, further expanding its compatibility and broadening its appeal to the growing market of home and small business users.

Consequently, the Commodore 128’s innovative features and success contribute to its lasting legacy as a significant and influential development in the history of personal computing.


The Commodore 128, introduced in 1985, served as a versatile and powerful personal computer catering to various needs of users at the time, ranging from home computing to educational and professional assignments. Its purpose was to operate as an advanced successor to the widely popular Commodore 64 while retaining its compatibility.

With capabilities such as multiple programming languages, video output formats, and distinctive modes of operation, the Commodore 128 aimed to address the growing demands of a diverse user base and facilitate access to computing resources for a wider audience. In fulfilling its purpose, the Commodore 128 provided users with advanced features that greatly expanded the possibilities of creative computing applications.

Equipped with an integrated keyboard, ports for connecting peripherals, and significantly increased memory capacity (128KB, expandable to 512KB), the machine allowed users to develop software, create and enjoy video games, compose music, produce animations, and manage databases, among other applications. The Commodore 128’s flexibility and accessibility were hallmarks of the era, exemplifying the rapid innovation and growth of personal computing in the 1980s.

Examples of Commodore 128

The Commodore 128 (C128) was an 8-bit home computer developed and launched by Commodore Business Machines in

Here are three real-world examples of how the technology was used:

Gaming: Like its predecessor the Commodore 64, the C128 provided an affordable and accessible platform for home gaming, supporting popular titles such as Bubble Bobble, Oregon Trail, and Paperboy. Users could easily connect the C128 to a television screen and use joystick controllers to play games with friends and family.

Personal productivity: The C128 featured a BASIC interpreter that enabled amateur programmers to create and run custom applications for various tasks, such as word processing, spreadsheet management, and database creation. Software titles like GEOS (Graphic Environment Operating System) could be used to perform tasks like drawing, painting, and even desktop publishing.

Education: Thanks to its affordability and user-friendliness, the C128 found a place in classrooms as a tool for learning both computer literacy and programming languages. Students could practice programming in BASIC or even upgrade to the more advanced Z80 assembly language using CP/M mode. This exposure to computing spurred many students to pursue careers in technology.

Commodore 128 FAQ

What is the Commodore 128?

The Commodore 128 (C128) is an 8-bit home computer introduced in January 1985 as an improved version of the Commodore 64. It offers three modes of operation: C128 mode, where it operates as a fully independent computer with additional memory and functionality; C64 mode, offering backwards compatibility; and CP/M mode, where it runs CP/M operating system applications.

What are the key features of the Commodore 128?

The key features of the Commodore 128 include 128KB of RAM, expandable to 512KB, built-in BASIC 7.0 with full-screen editor, an enhanced keyboard, built-in machine language monitor, 80-column RGBI video output, and the ability to run Commodore 64 and CP/M software.

What kind of software was available for the Commodore 128?

There was a range of software available for the Commodore 128, including productivity tools, programming languages, business applications, educational programs, and games. While the native C128 library was smaller compared to the C64, the C128’s compatibility with the earlier model allowed access to a vast software library of its predecessor.

How does Commodore 128’s compatibility with the Commodore 64 work?

The Commodore 128 includes a special 64 mode that enables it to run the vast majority of Commodore 64 software. By switching to the 64 mode, the C128 turns off its additional memory and features, simulating the environment of a Commodore 64 system so that older software may run seamlessly.

What is the difference between the Commodore 128 and the Commodore 128D?

The Commodore 128D is an updated version of the original C128. It comes in a redesigned case that accommodates both the computer’s mainboard and an integrated 1571 floppy disk drive. The C128D also features a detachable keyboard, improving its ergonomics and making it more of a desktop-style computer.

Related Technology Terms

  • 8-bit home computer
  • CP/M compatibility
  • MOS 8502 and Z80 microprocessors
  • VIC-II and VDC video chips
  • Commodore BASIC 7.0

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