Osborne Vixen
 | |
| Osborne Vixen portable computer | |
| Specifications | |
|---|---|
| Manufacturer | Osborne Computer Corporation |
| Type | Portable Computer |
| Released | November 1984 |
| Discontinued | 1985 |
| Intro price | US$1,298 (1984) |
| CPU | Zilog Z80A @ 4 MHz |
| Memory | 64 KB RAM |
| Storage | Dual 5.25" double-sided, double-density floppy drives (400 KB each) |
| Display | 7-inch monochrome CRT, 80×24 text |
| Sound | Internal beeper |
| Dimensions | 12.5" × 16.25" × 6.75" |
| Weight | 18 lbs (8.2 kg) |
| OS / Firmware | CP/M 2.2 |
| Predecessor | Osborne Executive |
| Codename | Encore |
| Model no. | OCC-4 |
The Osborne Vixen is a Z80-based portable computer introduced by Osborne Computer Corporation in late 1984 as the successor to the Osborne Executive. Designed as a compact, luggable CP/M system, the Vixen featured a larger screen, increased storage, and improved portability for business users.
Architecture and Processor
[edit | edit source]At its core, the Osborne Vixen utilised the Zilog Z80A microprocessor running at 4 MHz. The Z80A was a popular 8-bit CPU for CP/M systems, offering robust performance for business and productivity applications of the era.
The system architecture included:
- Z80A CPU @ 4 MHz
- 64 KB DRAM (maximum addressable by CP/M)
- Standard CP/M 2.2 BIOS and BDOS
- ROM for boot and system diagnostics
Memory and Storage
[edit | edit source]The Vixen shipped with:
- 64 KB RAM – the maximum supported by CP/M 2.2, used for operating system, applications, and RAM disk.
- Dual 5.25" floppy drives – double-sided, double-density, each offering 400 KB of storage (total 800 KB).
- Optional external 10 MB hard disk (Osborne "Hard Disk Subsystem"), connected via IEEE-488 interface.
The floppy drives supported standard CP/M disk formats, and the system could emulate a RAM disk for faster temporary storage.
Display and Graphics
[edit | edit source]The Osborne Vixen featured a:
- 7-inch monochrome CRT display
- 80 columns × 24 rows text mode
- Green phosphor screen, non-graphics (text-only)
The larger screen was a significant improvement over the Osborne 1's 5-inch display, allowing full-width CP/M text editing and spreadsheet work.
Sound Capabilities
[edit | edit source]Sound on the Vixen was limited to a simple internal beeper, used for system alerts and keypress feedback. No advanced audio hardware or synthesis was provided.
Input/Output and Expansion
[edit | edit source]The Osborne Vixen included a variety of I/O ports and expansion options:
- Parallel port (Centronics-compatible) for printers
- Serial port (RS-232C) for modems and terminals
- IEEE-488 port for external hard disk subsystem
- Composite video output for external monitor connection
- Keyboard – detachable, full-stroke, 69-key layout with numeric keypad
Expansion was limited compared to desktop CP/M systems, but the Vixen's ports allowed connection to most business peripherals of the era.
PCB Schematics & Service Manual
[edit | edit source]| Main Logic Board & IO | Schematics |
|---|---|
  |
File:Vixen Schematic.pdf |
The official Osborne Vixen Service Manual and full schematics are available on the Osborne Documentation category page
Gallery
[edit | edit source]-
Osborne Vixen portable computer (front view) -
Rear panel with I/O ports -
Main logic board
