Osborne Executive

Osborne Executive

Osborne Executive portable computer
Specifications
Manufacturer	Osborne Computer Corporation
Type	Portable Computer
Released	1982
Discontinued	1983
Intro price	US$2,495 (1982)
CPU	Zilog Z80A @ 4 MHz
Memory	128 KB RAM
Storage	Dual 5.25" double-sided, double-density floppy drives (each 360 KB)
Display	7" amber monochrome CRT (80×24 text)
Sound	None
Dimensions	18.5" × 11.25" × 7.5"
Weight	28 lbs (12.7 kg)
OS / Firmware	CP/M 2.2
Predecessor	Osborne 1
Successor	Osborne Vixen
Model no.	OCC Executive

The Osborne Executive is a portable CP/M-based computer released by Osborne Computer Corporation in 1982 as the successor to the Osborne 1. It featured a larger screen, more memory, and enhanced storage capacity, targeting business users seeking improved portability and performance.

🧠 Architecture and Processor

At its core, the Osborne Executive utilised a Zilog Z80A microprocessor running at 4 MHz. This 8-bit CPU was widely used in CP/M systems of the era, providing compatibility with a large library of business and productivity software.

The system architecture was designed to maximise performance within the CP/M environment, supporting bank-switched memory to address up to 128 KB of RAM—double that of its predecessor.

💾 Memory and Storage

The Executive shipped with:

• 128 KB RAM (bank-switched, with 64 KB accessible at a time under CP/M 2.2)
• ROM containing the boot loader and system utilities

For mass storage, the Executive featured:

• Dual 5.25" double-sided, double-density floppy drives
  • Each drive stored up to 360 KB per disk, for a total of 720 KB of removable storage.
• No internal hard disk; all storage was floppy-based.

🖥️ Display and Graphics

A key improvement over the Osborne 1 was the Executive's display:

• 7-inch amber monochrome CRT
• 80 columns × 24 rows of text (compared to the Osborne 1's 52×24)
• No bitmap graphics capability; text-only output

The larger, higher-resolution screen made the Executive more suitable for word processing and spreadsheet applications.

🔊 Sound Capabilities

The Osborne Executive did not include dedicated sound hardware. Any audio output was limited to system beeps generated by a simple internal speaker.

🎮 Input/Output and Expansion

The Executive provided a range of I/O ports for peripheral connectivity:

• IEEE-488 (GPIB) port for printers and external devices
• RS-232C serial port for modems and serial peripherals
• Parallel (Centronics) port for printers
• Video output for external monitor (monochrome composite)
• Keyboard – detachable, full-stroke, 69-key keyboard with numeric keypad
• Expansion slot for optional modem or other add-ons

The system was bundled with a suite of productivity software, including WordStar, SuperCalc, and dBase II.

🔍 PCB Schematics & Service Manual

The Osborne Executive's hardware comprised a main logic board and a separate power supply board. Detailed schematics and service documentation were provided to support field repairs and upgrades.

Main Logic Board	Logic Board Schematics
Osborne Executive Main Logic Board	File:Osborne Exec Schematic.pdf

For full service documentation, see the Osborne Documentation category.

📷 Gallery

• 
  Osborne Executive portable computer (open)
• 
  Osborne Executive with keyboard detached
• 7" amber CRT display (80×24 text)
  7" amber CRT display (80×24 text)
• 
  Main logic board
• Power supply board
  Power supply board

🧪 Related Pages

• Osborne Executive Maintenance Guide
• Osborne Executive Troubleshooting Guide
• Osborne Executive Keyboard Repair Guide
• Osborne Executive Capacitor Replacement Guide