The XT-IDE project is a Vintage Computer forum driven project to develop and manufacturer an 8-bit ISA IDE controller. It allows any PC/XT class machine to use modern IDE hard drives or Compact Flash devices for long term storage.
Our version of the XT-IDE controller replaces the 7400-series logic chips on the Vintage Computer forum design with a CPLD, a chip that can be programmed to replace dozens of individual logic chips. The logic is designed in software by drawing a schematic, and then uploaded to the CPLD. New logic circuits can be designed and tested without making new hardware each time.
A big thanks to pietja, J1mbo, alanh, and Vimark for helping out with this design.