Anthony, Piers. Split Infinity. Book One of the Apprentice Adept series. New York: Del Rey, 1987 (mass market pb).
Juxtaposes high-tech, feudal-capitalist world of Proton with the fantasy world of Phaze, where magic works. See for comparison and contrast of self-willed humanoid robots and AI (especially a lead female humanoid robot) and unicorns and werewolves, especially a lead female unicorn, with one alternative shape of a woman. Short-person Erlich also notes sympathetic handling of height and body size, and condemnation of the prejudices against the small (as in the hero Stile) and the very large (the helpful buddy, Hulk); that's not relevant for the human/machine interface, but it's bloody-well about time that popular literature dealt with us short people who "got no reason to live" (as Randy Newman satirically saith).
3. FICTION, RDE, 14/II/11