2-Port Expansion Card ISA RS232 Serial and Parallel Port - Retro I/O

In this review the 2-Port Expansion Card is presented as a purpose-built solution for owners of vintage PCs with an ISA slot who need reliable RS232 serial and parallel connectivity. The bottom line: it is for hobbyists and technicians restoring or operating 8086 through Pentium-era machines and embedded controllers, because it provides two RS232 serial ports and a DB25 parallel port using only a single 5V supply. The reviewer found it straightforward to install and focused on compatibility with legacy peripherals rather than modern plug-and-play conveniences.

Key Features

• Retro ISA interface: Works with classic 8086, 80286, 80386, 80486 and Pentium era motherboards that still expose an ISA slot, enabling legacy system restoration.
• Dual serial ports: Supplies COM1 as a DB9 port and COM2 via a pin header so users can connect two RS232 devices simultaneously.
• Parallel output: Includes an LPT1 DB25 parallel connector for printers and older scanners that require parallel port access.
• Single 5V power: Requires only a 5V supply to operate, simplifying installation in retro builds and reducing compatibility issues with older power rails.
• Industrial and peripheral use: Intended for real-world devices such as point of sale terminals, PLCs and scientific sensors that still rely on RS232 or parallel interfaces.

Who It's For

This card is aimed at vintage computer enthusiasts, refurbishment shops and technicians who maintain industrial or laboratory equipment that depends on RS232 and parallel connections. It is particularly useful for anyone running an 8086 through Pentium-era PC or a Celeron motherboard that retains an ISA slot and needs straightforward I/O expansion.

It is not geared toward mainstream desktop users or modern laptops that lack ISA slots, and those seeking USB-to-serial adapters or modern multiport networked serial devices should look elsewhere. The card assumes familiarity with installing internal ISA add-in cards and connecting external brackets and cables.

Pros & Cons

Pros

• Provides native RS232 COM1 and COM2 connectivity suitable for legacy peripherals and industrial gear.
• Includes a DB25 parallel LPT1 port for older printers and scanners, preserving compatibility with legacy workflows.
• Single 5V power requirement keeps installation simple on older systems and dedicated retro builds.
• Compact ISA design fits directly into vintage motherboards without extra adapters.

Cons

• Limited to systems with an ISA slot, so it will not work in modern PCs or laptops without additional hardware.
• COM2 uses a pin header rather than a second standard DB9 port, which may require an adapter or custom wiring for some devices.

Specifications

Interface	ISA
COM1 Serial	DB9 RS232
COM2 Serial	Pin header RS232
LPT1 Parallel	DB25
Power	5V
Included	1 ISA RS232 Serial and Parallel Port Card

Our Verdict

The 2-Port Expansion Card is a pragmatic, value-oriented option for anyone restoring or maintaining ISA-based systems and legacy equipment. It delivers the essential serial and parallel connections with minimal fuss and a single 5V power requirement, making it a sensible purchase for hobbyists and technicians who need genuine RS232 and LPT support rather than modern substitutes.

Frequently Asked Questions

Does this card require any drivers?
The card is a hardware I/O expansion for ISA systems; most vintage operating systems recognize standard RS232 and parallel ports but specific drivers may be required by particular software or OS versions.

Can both serial ports be used at the same time?
Yes, COM1 (DB9) and COM2 (pin header) are both RS232 ports and can operate simultaneously when properly connected and configured.

What power does the card need?
The board requires a single 5V power supply, which is typical for many retro motherboards and dedicated retro builds.