On Mon, Oct 1, 2018 at 1:17 PM Tapley, Mark via cctalk < [email protected]> wrote:
> > On Oct 1, 2018, at 1:55 PM, Paul Koning <[email protected]> wrote: > > > >> On Oct 1, 2018, at 2:46 PM, Ethan Dicks via cctalk < > [email protected]> wrote: > >> > >> On Thu, Sep 6, 2018 at 2:16 PM, Tapley, Mark via cctalk > >>> ...I have to say my favorite VT-100-alike is a Rainbow. One box (plus > monitor plus the dreaded LK-201), three functions in the collection: VT-100 > emulation (not perfect but not bad), CPM-80/86 (is that one or two > functions?), MS-DOS 3.11b. > >> > >> I have only recently learned of the built-in VT100 emulation. I'm > >> curious how it's "not perfect". > > > > I don't know that particular one. But a possible answer would be: > because the VT100 had a bunch of strange corner cases that were not > documented and not necessarily well understood. > > > > DEC created an internal standard for terminal behavior; that > specification was extremely detailed and very well written. It became the > functional specification for the VT200 series. I used it to write the > terminal emulator for RSTS on the Pro. It was understood at the time that > this spec was close to VT100 behavior (apart from 8 bit characters instead > of 7) but not exactly that, and deliberately so. > > > > Similar things have happened in other places. There is DDCMP, and "DMC > compatibility mode" which is best described as "DDCMP with certain bugs". > It hard to find a reasonable description of the latter. If you want to do > DDCMP, you're best off implementing the spec (which is easy) but if you do, > it won't work 100% with the "high speed" variant of the DMC-11. > > > > paul > > I can’t remember the exact VT-100 / Rainbow differences. I do remember > seeing a description (usenet-post kind of thing, not an official document) > that detailed them, and deciding the Rainbow emulation was “good enough” > for my purposes. If I can find that document (later this week) I’ll try to > post or re-post it, but I’m submerged by $work at the moment. If someone > else comes up with it before me, I’ll be glad! The TRM had a list of differences in it. They were both highly esoteric and generally not an issue for anything I ever ran on my Rainbow for the decade or so I used it. I don't think it mentioned DDCMP though. Warner
