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I have a Pascal program with a fair amount of inline assembly code in it which demonstrates the capabilities of «Электроника МС 7401» — символьно-графический видеотерминал (Elektronika MS 7401 - alphanumeric-graphical videoterminal), made in the Ukraine in the 1980s. Its commands were described in the Soviet magazine "Microprocessor Tools and Systems" (Микропроцессорные средства и системы) in 5/1989, but a scan of that issue that I could find online in a public library is incomplete, the article in question is missing. I was able to guess the meaning of only a fraction of the commands. Replacing them with PostScript, I got a few pictures.

Here is one of the pictures drawn by the program: An abstract pattern

Hoping that its commands follow a Western prototype, I'll provide a few translated code excerpts of the graphical primitives:

... obvious type definitions elided for brevity ...

(* Draws a line of the given type (solid/dotted/dashes, etc) to relative coordinates (PS rlineto) *)
procedure LINCUR(TYP,Х,Y:INТ);
begin
    WRIТЕ(’8’,TYP:0,' ',Х:0,' ',Y:0,BK)
end;

(* Same as above, but to absolute coordinates (lineto) *)
procedure LINE(TYP,Х,Y:INТ);
begin
    WRIТЕ(’7’,TYP:0,' ',Х:0,' ',Y:0,BK)
end;

(* Analog of PostScript moveto/rmoveto *)
procedure CURPT(ABS:ВООL;Х,Y:INТ);
begin
    if ABS then WRIТЕ(’4’) else WRIТЕ(’5’);
    WRIТЕ(' ',Х:0,' ',Y:0,BK)
end;

(* Draws a circle around the current point *)
procedure CIRCLE(TYP,R:INТ);
begin
    WRIТЕ(’>’,TYP:0,' ',R:0,BK)
end;

(* The coordinates are relative to the current point *)
procedure BOX(ХН,YН,ХВ,YВ:INТ);
begin
    WRIТЕ(’] ’,ХН:0,' ',YН:0,' ',ХВ:0,' ',YВ:0,BK)
end;

The end-of-command symbol BK was defined as ’≡125’ which raises doubts that the native encoding of the terminal was ASCII, but the commands themselves look reasonable.

Were there known Western graphical terminals using space-separated decimal coordinates, numerical commands for movement and line drawing, and numerical line type selectors?

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    I don't recognise the command style, but in the 80s there were possibly quite a number of command styles. Do you have reason to believe that the protocol was based on a Western model? One thing I can say though, is that it is not related to a Tektronix command language. – Greg Hewgill Dec 2 '20 at 1:16
  • @GregHewgill Its sibling Elektronika MS 7105 was a clone of DEC VT240, and most if not all Elektronika MS series had Western prototypes. – Leo B. Dec 2 '20 at 1:35
  • @LeoB. a footnote in the magazine the original poster refers to reads that the command system was created by a Soviet scientific research facility (Applied Math Institute of Academy of Sciences) – DmytroL Dec 2 '20 at 9:12
  • Here's also a LiveJournal of a guy who was doing something very similar back in 2016: spamsink.livejournal.com (is this you by any chance? :) ) so you can try to leave him a message in a comment to the pinned post. Here's a direct link to the post describing this guys' experiment: spamsink.livejournal.com/657185.html – DmytroL Dec 2 '20 at 9:18
  • As for Western graphics terminals, I believe this manual could be a decent reference on several of the escape sequence sets used: docs.attachmate.com/reflection/14.0/rvtref.pdf – DmytroL Dec 2 '20 at 9:29
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If you can read Russian, here is a complete scan of the magazine issue you're referring to:

In DjVu page numbering, the first page of interest is page 45.

I am not sure though if the article in question would give you much useful info as it does not contain any detailed command reference.

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  • Thanks for the reference! Alas, no details there. – Leo B. Dec 2 '20 at 9:55

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