Ultima II for Atari 8bit computers had no joystick support - keyboard only. So I had to implement it using my very limited 6502 assembly skills.
I liked Ultima I very much but was disappointed in Ultima II that it only allows using keyboard for player's character movements, the keys used are clunky and totally voided any pleasure from the game play. So for about a year I couldn't play Ultima II on my Atari 800 XE even though I badly wanted to. I was looking for perhaps a patched version that would support joystick - but no, no such version existed. So I had to do it myself as a result of my 6502 assembly language studying
Use the patched "Program Disk" image attached. Please note it doesn't include the entire game, you'll find the entire Ultima II game here: https://www.atarimania.com/game-atari-400-800-xl-xe-ultima-ii_5593.html