A series of blog posts by Carl Claunch starts here:
or maybe one post earlier, in the second part of this post:
(Click on Newer Post to walk forwards through the series)
There's really quite a journey from having printouts to understanding the machinery.
Quote:
RECREATING ORIGINAL FORTH IMPLEMENTATION ON IBM 1130
When Charles Moore created the FORTH language, it was famously done on an IBM 1130 whose restriction of file names to five characters forced Chuck to make his fourth generation language name become FORTH.
I have been in contact with Chuck and the Silicon Valley FORTH Interest Group (SV-FIG) to try to recover the original code. It looked like no copy existed until I discovered an obscure reference from 2011 on the 1130 google group which suggested that Chuck did send some code to a friend of mine.
I contacted Bob Flanders, who dug through his old email and discovered a previously unnoticed attachment which contained sixteen scanned images. These were twelve pages of an IBM 1130 assembler run and four pages of cryptic FORTH-like code.
I typed in the sixteen pages to make them machine readable, then Bob and I began to attempt a resurrection. The assembler program implements some basic primitives in FORTH, then reads card images from a fixed location on a disk drive which we believe are the contents of the four cryptic pages.
via monsonite on retrocomputingforum
where you'll also find links to the 12 pages of scanned printout as shared by Chuck Moore himself.