I should probably "learn assembly" one day.
I just wanted to make fan-content for my fandom, and stumbled onto ram edits that I wanted to apply to rom, such as moving items around, changing values, ect. So, I looked up documentation on Romhacking and eventually PS1 debuggers.
I honestly keep a chart of what "basic assembly functions" do for MIPS r3000, as well as x86 (no$psx uses x86 syntax for some reason), but I don't know barely anything about it except to read what's in front of me and calculate backwards what the PSX is getting it's numbers from. Where the memory address is, where the code that fills it is, ect.
Other than that, I don't know anything about "opcode", except "what" it is.