Nascom 2

The Nascom 2 developed the original kit into a faster and more expandable Z80 computer. It retained the single-board format and full keyboard while adding more memory, improved video circuitry and Microsoft BASIC in ROM.

Four configurable memory sockets and the Nasbus expansion connector made the machine a flexible foundation for disk controllers, graphics boards and additional RAM. Like its predecessor, it was supplied with extensive technical documentation for builders.

Notable Features

• Microsoft BASIC and monitor firmware could reside in on-board ROM.
• Configurable sockets accepted RAM or ROM to suit the owner’s system.
• Nasbus expansion supported disk, memory and specialist interface cards.

Historical Significance

• Turned the pioneering Nascom concept into a more capable general-purpose computer.
• Its open, modular design helped sustain a strong British hobbyist and small-business community.

Collector’s Notes

• RAM and ROM configurations differ widely because owners expanded their machines.
• Inspect the board for modifications and verify which monitor and BASIC ROMs are fitted.

Specifications

Technical Information
Name	Nascom 2
Manufacturer	Nascom
Launched	Monday, January 1, 1979
Country	United Kingdom
CPU	Zilog Z80A at 2 or 4 MHz
Units Sold
Operating System	NAS-SYS monitor, Microsoft BASIC; CP/M or NAS-DOS with disk expansion
I/O	RS-232, video, RF, TTY, parallel I/O and Nasbus expansion
Keyboard	Full alphanumeric keyboard
Storage	300/1200-baud cassette; optional 5.25-inch floppy drives
Sound	Programmable output; sound depended on expansion
Graphics	Programmable-character monochrome display; expansion graphics available
Display	Video or RF output; typically 48 x 16 text
ROM	Approximately 10KB including NAS-SYS and 8KB Microsoft BASIC
RAM	10KB typically installed; up to 32KB on board and more through expansion
CPU Speed	2 or 4 MHz