Hi Graham, Prompted by that KDF9 post to the mailing list, I did a bit of googling, and ran across David Green's First Generation computers website. I'd seen it before, but I'd never noticed that his page on the EE Deuce has links to the KDF9 Programming Manual, along with a small User Code Digest booklet. http://members.iinet.net.au/~dgreen/deuce/deuce.html As best as I can tell, the PM is the same one that Mike Jeays photoed, except this one is a PDF produced from much higher quality scans. You might want to snarf a copy of the PM for history.dcs.ed.ac.uk. http://acms.synonet.com/deuce/KDF9pm.pdf (PDF, 12MB) Incidentally, I noticed when trawling through the archives a little while ago that you had a copy of Luke McConnell's Java KDF9 emulator. Alas, it's quite incomplete, and going by a decompilation of the Java, is actually an interpreter for a subset of the User Code language rather than a machine emulator, but it's curious nonetheless. Could you tell me anything more about it? How did you find it? Who is this Luke fellow? Cheers, Brian.