Commodore 128D

Released: January 1986 Original Price: $499.95

Gallery

Commodore 128D computer The sleek Commodore 128D with its built-in 1571 floppy drive and detachable keyboard.

C128D rear view The rear panel showing the extensive connectivity options of the 128D.

C128D setup A complete C128D workstation with monitor and printer.

Commodore 128D

“The 128D was Commodore’s answer to the desktop PC. It was everything the 128 was, but in a professional package that looked at home in any office. That built-in 1571 drive made it a dream to use.” - Bil Herd, Commodore Engineer

The Commodore 128D (C128D) was the desktop version of the popular Commodore 128, released in 1986. Featuring an all-in-one design with a built-in 1571 floppy drive and detachable keyboard, the 128D offered a more professional appearance than its breadbox-style sibling while maintaining full compatibility with both C128 and C64 software. It represented Commodore’s attempt to compete with business-oriented computers like the Apple IIe and IBM PC.

The Professional 8-Bit

The 128D was designed to bridge the gap between home and business computing. Its sleek, beige case and professional appearance made it suitable for office environments, while its three operating modes (C128, C64, and CP/M) provided exceptional software compatibility.

Key Features

Built-in 1571 Floppy Drive: Faster and more reliable than the 1541
Detachable Keyboard: Full-travel keys with numeric keypad
Multiple Video Outputs: Composite, RGBI, and RF
128KB RAM: Ample memory for business applications
Three Operating Modes: C128, C64, and CP/M 3.0

Technical Specifications

CPU: MOS 8502 @ 2 MHz (1 MHz in C64 mode) + Z80 @ 4 MHz (CP/M mode)
Memory: 128 KB RAM (bank-switched) + 72 KB ROM
Graphics: VIC-II (40/80 columns, 320×200, 16 colors) + VDC (640×200, 16 colors in 80-column mode)
Sound: SID 8580 (3 channels, 4 waveforms, filter, ADSR)
Storage: Built-in 1571 floppy drive (5.25", 360KB), optional external drives
Ports: Cartridge, serial, user, RGBI, TV/RF, composite, 2× joystick, power
Operating System: Commodore BASIC 7.0, C64 KERNAL, CP/M 3.0

Design and Features

Professional Aesthetics

All-in-One Design: Floppy drive integrated into the main unit
Detachable Keyboard: Full-travel keys with numeric keypad
Ventilation: Improved cooling over the original C128
Case Design: Sleek, professional look in light beige

Enhanced I/O

RGBI Output: For crisp 80-column text on compatible monitors
User Port: For peripherals and expansions
Serial Bus: For connecting additional drives and printers
Cartridge Port: For software and hardware expansions

Storage Solutions

Built-in 1571: 360KB double-sided floppy drive
Dual Drives: Could control a second external drive
Fast Load: Improved disk access speeds
CP/M Support: Read MS-DOS formatted disks in CP/M mode

The 128D Experience

For Business Users

Word Processing: SpeedScript, Vizawrite, WordPro
Spreadsheets: SuperCalc, Multiplan
Databases: File 2000, dBase II
Communications: Terminal programs for BBS access

For Programmers

BASIC 7.0: Advanced programming environment
Machine Language: Full access to hardware
CP/M Development: Tools for CP/M software
Demo Scene: Used for 128K intros and demos

For Gamers

Full C64 Compatibility: Access to thousands of games
Enhanced Games: Some titles took advantage of extra RAM
Better Loading: Faster disk access than tape-based systems

Technical Deep Dive

Motherboard Revisions

Original 128D (1986): Metal case, external power supply
128DCR (1988): Cost-reduced plastic case, internal PSU
128D-ALPS: Different keyboard mechanism
128DCR-00: Final revision with fewest chips

Memory Architecture

Bank 0: 64K (shared with VIC-II)
Bank 1: 64K (accessible when VIC-II isn’t using the bus)
ROM: 32K BASIC + 32K KERNAL + 8K character ROM
I/O Area: Memory-mapped I/O registers

Video Modes

40-Column: 320×200, 16 colors, 8 sprites (VIC-II)
80-Column: 640×200, 16 colors (VDC)
Composite: For standard TVs
RGBI: For professional monitors

The 128D Legacy

Commercial Performance

Markets: Strong in Europe and South America
Business Adoption: Used in offices and schools
Longevity: In production until 1989

Why It Stood Out

Professional Design: Looked at home in offices
Built-in Drive: No separate disk drive needed
CP/M Compatibility: Access to business software
C64 Mode: Huge software library

Collector’s Item

Desirability: Highly sought after
Price Range: $200-$800 depending on condition
Rarity: Less common than standard C128

Notable Software

Business

GEOS 128: Graphical operating system
Superbase 128: Database
VizaWrite: Word processor
SuperCalc 3: Spreadsheet

Development

Merlin 128: Assembler
BASIC 7.0: Built-in programming
Machine Language Monitor: For low-level programming

Games

The Bard’s Tale: RPG
Elite: Space trading game
SimCity: City-building simulation
Arkanoid: Breakout clone

Technical Notes for Enthusiasts

Common Issues

Power Supply: Original PSUs can fail
Keyboard: Keycaps can yellow
Floppy Drive: Heads may need cleaning
Chips: PLA and SID chips can fail

Modern Upgrades

RAM Expansions: Up to 2MB
Storage: SD card solutions
Video: RGB to HDMI converters
Networking: Ethernet interfaces

The 128D Today

Emulation

VICE: Full 128D emulation
MAME: Arcade emulation with 128D support
FPGA: Hardware-accurate recreations

Community

Forums: Active discussions
Events: Retro computing meetups
Development: New software and hardware

Did You Know?

The 128D was originally going to have a built-in 3.5” drive
Some 128Ds were sold with a matching monitor (the 1902)
The 128D’s case was designed to match the Amiga 2000
A rare variant called the 128D-80 was planned with an 8088 processor for PC compatibility
The 128D was used in some Eastern European schools well into the 2000s

The 128D in Popular Culture

Featured in the movie “The Manhattan Project” (1986)
Appeared in the TV show “Mr. Robot” as part of a retro computing setup
Used by author William Gibson while writing parts of the “Sprawl” trilogy