[Info-vax] escape sequences, cursor positioning

[sol gongola]

Jan-Erik Söderholm wrote:
> SMS wrote:
>> Jan-Erik Söderholm wrote:
>>> SMS wrote:
>>>> JF Mezei wrote:
>>>>
>>>>> DECTERM doesn't do display control characters. [...]
>>>>    I believe that mine do.  I've just been using
>>>> EDIT /TPU to look at a log file from  a
>>>> "SET HOST 0 /LOG" command, and I see a
>>>> whole collection of cute little [C/R] and [N/L]
>>>> characters on my screen.
>>> Aren't they displayed by TPU, not by the DECTerm ?
>>> That is, when they are sent to DECTerm, they are not
>>> control characters but the actual characters "C", "/",
>>> "R" and "N", "/", "L".
>>
>>    No, I mean single-cell characters which look roughly like:
>>
>>       +--+      +--+
>>       |C |      |N |
>>       | R|      | L|
>>       +--+      +--+
>>
>>    As for who's displaying them, well, TPU/EVE is telling the DECterm
>> what to do, and the DECterm is doing it.  According to my handy "VT
>> 220
>> Programmer Pocket Guide", these are in the DEC Special Graphics
>> character set
> 
> Right then, then they are still not "controll characters".
> It's still something TPU is sending to be displayed, not
> true CR and LF characters...
> 
> What JF was talking about was when the term-emulator
> displays "C/R" (or similar text) instead of actualy
> performing the "carriage return" or "line feed" operation.
> 
> Jan-Erik.
> 
> 
>  (with all the L- and T-shapes in different orientations,
>> and the horizontal lines at five different heights, and the rest of
>> the
>> fun stuff).  Anyone doing serious VT100 graphics needs to know about
>> these (and the SO (%x0E) and SI (%x0F) characters to switch back and
>> forth between G0 and G1).  (It's all in the book, and I haven't really
>> cared since about 1985.  And thanks for reminding me.)
>>
>> --------------------------------------------------------
>>
>>    Steven M. Schweda               sms at antinode-info
>>    382 South Warwick Street        (+1) 651-699-9818
>>    Saint Paul  MN  55105-2547

The cr lf characters are displayed when they are outside the standard crlf sequence.