IBM 1501485 ISA Async Communications Adapter Card Dual Serial Port

IBM 1501485 ISA Async Communications Adapter Card Dual Serial Port

This is an asynchronous serial communications adapter card designed for IBM PC, XT, AT, and compatible computers with ISA bus slots. The 1501485 provides dual RS-232 serial ports for connecting modems, printers, terminals, and other serial peripherals to vintage IBM systems. These adapters were standard components in legacy business and technical computing environments throughout the 1980s and early 1990s.

Specifications & What's Included

• IBM Part Number: 1501485
• Type: ISA 16-bit asynchronous communications adapter card
• Interface: ISA slot connector (gold-plated fingers)
• Serial Ports: Two RS-232 serial ports (asynchronous)
• Connector Type: DB-9 or DB-25 serial connectors (depending on variant)
• Protocol Support: Asynchronous serial communication, full-duplex capable
• Compatible Platforms: IBM PC, XT, AT, PS/2, and ISA-compatible systems
• Form Factor: Full-size ISA expansion card
• Condition: Tested and in good working condition

Applications

The IBM 1501485 async adapter was widely used in business computing environments to add or expand serial communication capabilities on IBM systems. In the 1980s and early 1990s, serial ports were the primary interface for connecting modems, connecting to mainframe systems via X.25 or async protocols, attaching serial printers and plotters, and linking to laboratory or industrial test equipment. This card was particularly common in data communications, terminal emulation, and remote access setups where computers needed multiple simultaneous serial connections. The adapter remains compatible with any ISA-bus system that supports legacy serial communication, making it useful for vintage system restoration and retro computing projects.