The Glitch Works XT-IDE rev 4 is an open-source 8-bit ISA IDE controller board that enables the use of modern 16-bit IDE devices (CompactFlash adapters, DOM modules, hard drives) on vintage IBM PC/XT, AT, and compatible systems. Designed in KiCad and licensed under GNU GPL v3.0, the rev 4 improves on the rev 3 with better silkscreen, larger jumper pads, corrected latch read/write timing, additional Slot 8 Support test points, and consistent parts numbering for easier kit assembly. When paired with the XTID

Bus Interface

8-bit ISA (fits any PC/XT/AT 8-bit slot)

Storage Media

IDE/ATA — CompactFlash via adapter, DOM, or standard IDE hard drive

Design Tool

KiCad (fully open-source EDA)

License

GNU GPL v3.0

PCB

2-layer, ISA form factor, through-hole components

DIP Switch Banks

2x CTS 208-8 (8-position each) for address configuration

EEPROM

AT28C64B (8KB, 28-pin DIP) — in-system programmable

Bus Transceivers

2x 74LS245 octal bidirectional transceivers

Latches

2x 74F573 octal transparent latches

Address Decoders

2x 74LS688 8-bit magnitude comparators

Logic ICs

74LS138 3-to-8 decoder, 2x 74LS04 hex inverter, 74LS32 quad OR gate

Pull-up Networks

2x 10Kx9 SIP resistor networks (RP1, RP2)

Bypass Capacitors

11x 0.1uF axial ceramic + 1x 100uF 6.3V electrolytic

Activity LED

HP HLMP-3507 with 470R current limiting resistors

BIOS

XTIDE Universal BIOS — GPLv2, supports up to 4 IDE controllers

Revision

Rev 4 (2017) — improved timing, silkscreen, and Slot 8 test points

LIM 4.0 focused EMS board and backplane line for pre-386 platforms, designed for deterministic page-frame mapping and predictable software compatibility.

Standard

LIM EMS 4.0 page-frame compatibility

Frame Windows

D000h and E000h profile sets

Capacity Range

2MB to 8MB banked architecture

Configuration

Register maps with conflict-safe presets

Validation Suite

Lotus 1-2-3, QEMM, DOS extender scenarios

Deployment Form

Single-card and modular backplane builds