Are HP 48 library structures documented?

[rprosperi]

Get Joe Horn's Goodies disk #4 (in fact, get all 11 disks) from hpcalc.org, and look at the file usrlib.doc (which is actually a text file, not a word doc). This is the official doc from HP on this.

As Ray mentioned though, there are many enhanced tools/docs since this original, almost all of which are on hpcalc.org (thanks Eric!).

Two essential docs you will need, if you plan to touch SysRPL are Jim Donnelly's "Grey BooK" aka "Introduction to System RPL and Assembly Language" (48 series) and "Programming in System RPL" by Kalinowski (2nd Edition covers 48/49g/49g+/50g).

Not light reading, but they cover all you will need (and more...)