I realized I did not know anything about the RST instruction. Is it kind of special CALL instruction ? Does it have to be used only when dealing with interrupts ? etc. Thanks to pulkomandy who had to dig deeply around it while working on its Caprice Reloaded project, he was able to give me some precise details about it. I found our conversation so interesting that I finally decided to make a dedicated article about it. You can read the article here (also added in Articles section).