ISA expansion boards

Recreates the circa-1990 AdLib OPL2 FM-synthesis sound card as a buildable open hardware project.

For this platform (bus/interface): The board design uses an ISA bus connector and the standard AdLib I/O address region. No narrower 8-bit or 16-bit compatibility tag is assigned without a clearer host-width statement.

This is a self-assembly reproduction rather than a currently sold assembled card. The repository has no packaged release; use the project files and parts list directly.

Recreates the Gravis Ultrasound PnP ISA sound card around an AMD InterWave chip, with an optional IDE CD-ROM interface.

For this platform (bus/interface): The project explicitly identifies this as an ISA card, not EISA. The optional IDE CD-ROM function uses a programmed 16V8 GAL for bus buffering and address decoding.

The maker has not fabricated or tested this board and has not generated a fabrication package. It also requires an AMD AM78C201 InterWave chip. Treat it as an experimental design and build at your own risk.

Open ISA controller that connects ATA or IDE drives to an XT-class computer.

For this platform (bus/interface): This is an ISA controller for XT-class computers. Confirm the host's available slot, address configuration, firmware requirements, and compatibility with the selected ATA or IDE device.

Retro Electronics listed the bare Revision 4 PCB in stock on 2026-07-25. The builder must source the components, assemble the card, and follow the project instructions; no current kit or assembled-board availability was verified.

Provides MDA and CGA-compatible display modes with 31 kHz VGA output for modern monitors and capture devices.

For this platform (bus/interface): The repository identifies this as an ISA video card. It can emulate MDA or CGA and provide standard-frequency VGA output, with mode and hardware options configured on the card.

This is a self-assembly project. The maker advises checking for shorts between each power rail and ground before installation; the oscillator configuration also affects CGA composite color accuracy.

Open hardware reproductions of the two interface cards used to connect an IBM PC or XT to a 5161 Expansion Unit.

For this platform (exact target): These are 8-bit ISA interface cards, but the documented host application is specifically an IBM PC or XT connected to a 5161 Expansion Unit or a suitable replacement backplane.

Open RTL8019 Ethernet card that brings NE2000-compatible networking to 8-bit ISA computers.

For this platform (bus/interface): This is explicitly a 62-pin 8-bit ISA card and can also run in a 16-bit ISA slot at 8-bit speed. Choose free I/O, IRQ, and optional boot-ROM resources, and use the supplied patched driver for packet-driver software.

The fully assembled card was out of stock on Tindie on 2026-07-25 and had been sold out since December 15, 2025. Open KiCad files, Gerbers, software, and a separate bare-PCB path remain available. A DIY build needs a unique valid MAC address and surface-mount RTL8019 assembly.

Current 8-bit ISA adapter that lets a CompactFlash card serve as an XT-IDE hard disk in an IBM PC or XT-class computer.

For this platform (bus/interface): This is an 8-bit ISA CompactFlash adapter with an XT-IDE option ROM. Verify that the host BIOS can initialize option ROMs and that its configured I/O and ROM addresses do not conflict with other cards.

Open ISA controller with two floppy controllers for up to eight drives, plus optional serial and BIOS hardware.

For this platform (bus/interface): Choose nonconflicting IRQ, DMA, I/O, and option-ROM resources for the installed functions. Check the controller-chip limitations documented by the project before relying on FM encoding, tape support, or 1 Mbit/s operation.

The assembled and tested card was out of stock on Tindie on 2026-07-25 and had been sold out since January 31, 2026. Open KiCad files, Gerbers, a bill of materials, and a manual remain available. Optional 5 V-on-pin-3 jumpers are only for compatible PS/2-style floppy drives and can damage standard drives if installed incorrectly.

An 8-bit ISA card with switchable classic sound-card modes plus MIDI, USB game-controller, and CD-ROM emulation.

For this platform (bus/interface): PicoGUS is an 8-bit ISA card and does not support high DMA. The project requires an ISA bus speed of 8.33 MHz or lower and warns that chipset-specific DMA behavior varies. Choose free IRQ and DMA resources for the selected mode; PicoGUS 1.2 and 2.0 can leave DMA unassigned for modes that do not use it.

Joe's Computer Museum showed the assembled PicoGUS 2.0 in stock on 2026-07-24. The official site also listed stocked UK and EU sellers. Open design files and build guidance remain available for people who want a DIY board.

Current multifunction 8-bit ISA card that adds emulated storage, memory, networking, and USB or SD-connected devices to PC/XT-class computers.

For this platform (bus/interface): The current vendor page identifies PicoMEM as an 8-bit ISA expansion card. Its emulated RAM can be slower than native memory, so check the project's performance guidance for the intended host.

Adds an Apple II-compatible environment to an IBM PC through an ISA expansion card.

For this platform (bus/interface): Quapple is an ISA expansion card, but the project documents IBM 5150 and 5160 hosts rather than generic later ISA systems. Do not assume compatibility with faster PCs because the required Quadlink software may use CPU-dependent timing loops.

The author provides complete design and fabrication files but does not sell the board. This is a large full-length card with programmed logic, RAM and ROM parts, and several required cable assemblies. It also needs the original Quadlink software disk images and DOS. The clone has been tested only in an IBM 5150; the 5160 is expected to work but remains untested by the author, and faster ISA systems may fail because the software may contain CPU-dependent timing loops.

Open 8-bit ISA real-time clock card for PC/XT systems without a built-in battery-backed clock.

For this platform (bus/interface): Choose a free I/O address. The seller recommends 0x240 for general PC/XT-compatible systems; 0x70 is the default for Micro 8088 and NuXT v1.x systems.

Weird Electronics' assembled, complete-kit, and PCB-plus-programmed-SPLD options were temporarily unavailable while the seller takes a break through August 20, 2026. Aitor Gomez Garcia's low-profile version showed three units in stock on 2026-07-27 but currently ships only within Spain. A CR2032 battery is not included.

Open ISA card combining a two-drive floppy controller, RS-232 serial port, and optional BIOS ROM.

For this platform (bus/interface): Select free serial, interrupt, and option-ROM resources. An IBM AT may report error 601 when its original floppy controller is absent, although the project says it can continue after F1.

The repository supplies KiCad files, Gerbers, a bill of materials, and assembly documentation rather than a retail order path. Install the 5 V-on-pin-3 jumper only for a compatible PS/2-style drive; using it with a standard drive causes a short. Version 1.0 also has a documented option-ROM switch-table error.

Open ISA sound-card design using Yamaha OPL2 hardware for AdLib-compatible FM synthesis.

For this platform (bus/interface): The project is an ISA card for PC/XT-compatible systems and implements AdLib-compatible YM3812 synthesis. Confirm slot clearance, audio-bracket work, and availability of the YM3812 and YM3014B before starting a build.

Retro Electronics listed the Version 1.2 bare PCB in stock on 2026-07-25. No components or assembly are included; the obsolete Yamaha sound chips can be harder to source than the common logic and passive parts.

Schematic-only ISA Port 80h diagnostic display for troubleshooting PC hardware.

For this platform (bus/interface): The circuit monitors the conventional POST port 80h on an ISA bus. Its decimal decoder cannot display hexadecimal A through F normally.

This is a reference design, not a fabrication-ready kit. The page provides PDF and EAGLE schematics but no PCB layout, Gerbers, or bill of materials, so a builder must complete the hardware design.

Open Trident TVGA9000i VGA card for 8-bit ISA computers, including the original IBM PC and XT.

For this platform (bus/interface): The 8-bit card works in original PC/XT buses and in 16-bit ISA slots. Review the PCB-version errata and monitor-detection notes before assembly.

Use PCB version 1.1 for an original IBM PC or XT; version 1.0 needs the documented ALE rework. On version 1.1, the C17 silkscreen incorrectly says 1 uF instead of 1 nF. The project also documents a color-monitor detection workaround for newer DDC displays.

Recreates the 1989 Sound Blaster 1.0 with digital playback and recording, AdLib-compatible synthesis, CMS audio, and a joystick/MIDI port.

For this platform (bus/interface): The project is an ISA Sound Blaster 1.0 clone with configurable I/O address, IRQ, and DMA settings. Like the original card, it does not require the ISA -5 V rail.

This is a self-assembly project. Follow the documented bodge resistor, MIDI jumper-wire, firmware, DMA, IRQ, joystick, and I/O-address instructions before use.

DIY 8-bit ISA CompactFlash adapter that provides mass storage and supports an XT-IDE BIOS extension ROM.

For this platform (bus/interface): The project explicitly identifies the board as an 8-bit ISA interface. Choose free I/O and option-ROM addresses, and use a host BIOS that can initialize the extension ROM.

The project supplies build files and documentation rather than a direct retail order path.