Retro Computer System

NABU PC System Guide

The NABU PC was an early 1980s Canadian home computer built around the idea of delivering software and information through cable television infrastructure. This page serves as a central hub for NABU PC videos, hardware, software, network tools, documentation, and revival projects, with more in the full archive.

"Natural Access to Bi-directional Utilities" - NABU

Home Videos Systems Media & Collectibles Want List About Contact

NABU PC Videos, Hardware, and Resources

Explore the NABU PC, its original cable-network design, hardware, software, Internet Adapter tools, CP/M support, documentation, and related vintage computing projects featured in the Geek With Social Skills archive.

Videos and Projects

This section features Geek With Social Skills videos covering NABU PC hardware, software, CP/M experiments, MSX-related testing, network tools, and the modern NABU revival.

Back to top

NABU PC Resources and Downloads

The following external resources provide NABU PC software, ROM images, Internet Adapter tools, technical documentation, specifications, open source projects, and historical material.

NABU Network Resources

Guides and Documentation

Open Source and Development

Historical Archives

Back to top

System Overview

  • Introduced: 1983
  • Original Price: $950
  • CPU: Zilog Z80A running at 3.58 MHz
  • Memory: 64 KB DRAM
  • Video Memory: 16 KB DRAM
  • ROM: 4 KB EPROM standard, with 4 KB or 8 KB jumper selection
  • Video: Texas Instruments TMS9918 Video Display Processor
  • Sound: General Instrument AY-3-8910 programmable sound generator
  • Network Interface: RS-422 full duplex at 111 Kbits/sec
  • Keyboard: Full-stroke keyboard with Alps switches and two DB-9 joystick ports

Back to top

Technical Specifications

The NABU PC combines a Z80A processor with dedicated Texas Instruments video hardware, General Instrument sound, serial interfaces, expansion slots, and a high-speed RS-422 network connection designed for use with the original NABU cable network.

Video Display

  • Texas Instruments TMS9918 Video Display Processor
  • 16 KB dedicated video RAM
  • 256 x 192 graphics resolution
  • 40 x 24 text display
  • 32 sprite planes
  • 15 colors plus transparent
  • NTSC composite video output
  • Channel 3 or 4 RF output

Sound

  • General Instrument AY-3-8910 programmable sound generator
  • 3 sound channels
  • RF-modulated television audio output
  • External line-level audio output

Input, Output, and Expansion

  • Four internal card slots with 30-pin headers
  • 5-pin DIN RS-422 network serial interface
  • 6-pin DIN RS-422 keyboard serial interface
  • DB-15 8-bit parallel printer interface with handshaking
  • RCA composite video output
  • RCA audio output
  • Type-F RF input and output connectors
  • Two DB-9 joystick ports located on the keyboard

Back to top

History and Development

Natural Access to Bi-directional Utilities, or NABU for short, was an ambitious Canadian home computing project built around delivering software and information through cable television infrastructure. NABU rolled out its home computers in 1983 and launched network service in Ottawa on October 26 of that year.

The NABU PC connected through a cable adapter to a central network, allowing users to access programs and information without relying entirely on locally stored software. Available content included games, educational programs, financial tools, news, and programming languages such as LOGO.

The system was unusually forward-looking for the early 1980s, combining a home computer with centralized software delivery and online services years before internet access became common in homes.

Despite the technology and ambitious plans, the NABU Network struggled to attract enough subscribers. The original company encountered serious financial problems, and the successor network operation ultimately ceased service at the end of August 1986.

Back to top

NABU Computer Revival

The NABU PC experienced a surprising modern revival in late 2022 when a few thousand New Old Stock NABU units appeared on eBay through PellMill LLC. For vintage computing enthusiasts, it was a rare chance to buy an unused 1980s network computer decades after the original service had ended.

On November 26, 2022, Adrian Black posted a video on Adrian's Digital Basement titled "The 1980s computer you've never heard of - The NABU PC". Interest quickly grew around the newly available hardware and helped encourage another wave of development, preservation, documentation, and experimentation.

Today, the NABU community continues to explore original software, CP/M, network emulation, modern adapters, archival material, and new ways to use the hardware outside its original cable network environment.

Back to top

Related Videos

Explore More