Based on schematics by Sergey Kiselev, with some small changes for combining optimization and board layout efficiency:
https://www.malinov.com/Home/sergeys-projects/isa-fdc-and-uart
https://www.malinov.com/Home/sergeys-projects/xt-cf-lite
https://www.malinov.com/Home/sergeys-projects/isa-supervga