Update 2024-01-19: This has worked pretty well for a while, but you might be better served with my broadlink remote file. It supports more commands and features, and doesn't require the separate "on" ...

This document outlines how the AR-REG1U Fujitsu Mini-split IR remote encodes signals to send to the wall-mounted mini-split unit. It's entirely possible other Fujitsu remotes, or even other mini-split ...