I had a look at tcf.s, and it depends on having been loaded by the V6 disk bootstrap - it uses the console driver in the bootstrap (the bootstrap leaves a pointer to it in R5). So it might be easier to use that DTF.MAC, which seems like it's mostly the same program, and which you apparently already have working? If you'd still like to use the V6 tcf, due to the teletype driver issue, probably the easist thing is that I could make up a miniature disk image (RK05, if you have that available), with both the V6 bootstap, and tcf on it. Otherwise, I might be able to cobble something together; a hacked version of tcf including the console driver, or something like that. I know nothing of almost any DEC software, alas - I'm assuming it can handle .LDA files, but I don't know which format it prefers. Having just looked at the original :-), it did have two messages: "ready drive 0 and type y" and "tcf: error" (Shades of 'ed'.... :-) Noel