Zenith 85-3359-01 16-Bit ISA I/O Controller Board 070887 Long Card Vintage PC

Zenith 85-3359-01 16-Bit ISA I/O Controller Board 070887 Long Card Vintage PC

This is a full-length 16-bit ISA I/O controller board manufactured by Zenith, carrying part number 85-3359-01 and PCB date/revision code 070887, as silkscreened directly on the board. The card occupies a standard full-length ISA slot and provides I/O controller functions — including serial and parallel port connectivity — for Zenith desktop PC systems of the era that used 16-bit ISA expansion architecture.

Specifications & What's Included

• Manufacturer: Zenith
• Part Number: 85-3359-01
• PCB Code / Date Stamp: 070887
• Bus Interface: 16-Bit ISA
• Form Factor: Full-Length (Long Card)
• Bracket Connectors: DB-25 (parallel port) and DB-9 (serial port)
• Notable ICs: Hitachi HD14681BAP, Siemens SN74LS245N (multiple), Intel-marked logic ICs
• PCB: Green, fully populated with through-hole components
• Includes: Card only — no cables, manuals, or accessories

Applications

The 16-bit ISA (Industry Standard Architecture) bus was introduced with the IBM PC/AT in 1984 and became the dominant expansion standard for DOS-era desktop PCs through the late 1980s and into the early 1990s. I/O controller cards of this type provided the system with serial (RS-232) and parallel (Centronics/DB-25) port connections, which were essential for attaching printers, modems, and peripheral devices in that era. This specific board was designed for Zenith Data Systems desktop computers — Zenith was a major U.S. manufacturer of IBM-compatible PCs during the 1980s, widely used in business, government, and military installations. By the mid-1990s, ISA I/O functions were integrated directly onto PC motherboards, making standalone ISA I/O cards obsolete. Today these boards are sought by collectors and technicians maintaining or restoring vintage Zenith and compatible IBM AT-class systems.