[Info-vax] 8-bit characters

[Phillip Helbig undress to reply]

In article <smicj8$h9r$1 at gioia.aioe.org>, Michael Moroney
<moroney at world.std.spaamtrap.com> writes: 

> >>> notice that COMPOSE-T-H and COMPOSE-t-h create upper and lower case
> >>> thorn (Þ þ if those characters get through).  If entered by both
> >>> create the character, unless it is at the beginning of a line, in which
> >>> case one sees <XDE> or <XFE> (one character, displayed as several).
> >>> ASCII values are 222 and 254.  Refreshing the screen also causes the
> >>> mnenonics to appear.  Also, they are not displayed via HELP FORTRAN
> >>> CHAR DEC.
> >>>
> >>> Any deeper reason or just flaky instrumentation?
> >>>
> >>> I also notice that × (COMPOSE-x-x) works fine in a DECterm but not on a
> >>> real VT220 (where most or all other composed characters work).  Again,
> >>> deeper meaning or just flaky?
> >>
> >> You're definitely not looking at ASCII, and AFAIK Þ and þ aren't
> >> in DEC
> >> MCS,
> > 
> > At least HELP FORTRAN CHAR DEC doesn't show them.
> > 
> >> which likely means you're looking at inconsistent handling of or
> >> inconsistent configuration of ISO 8859-1 among your apps and OS and
> >> hardware; I'd guess some here is MCS, and some 8859-1.
> > 
> > Only LK411, Alpha hardware and DECterm (under CDE, but that's probably
> > irrelevant).  Maybe they are inconsistent.  :-|
> > 
> >> You've asked variations of this question over the years too, usually
> >> involving trying to use EDT past ASCII or maybe past DEC MCS.
> > 
> > Yes.  :-)
> > 
> The character set ISO-8859-1 is almost the same as DEC-MCS with some of 
> the undefined DEC-MCS characters being defined in ISO-8859-1.  The 
> exceptions are a few rarely used characters such as Œ and Ÿ. 
> Specifically, ISO-8859-1 has Icelandic Þ and þ, these positions are 
> undefined in DEC-MCS. 99% of the time one can use ISO-8859-1 instead of 
> DEC-MCS and get away with it.

Right.  And ISO-8859-15 is also similar.  I routinely write € in EDT to 
get the Euro sign when most people read that text.

> There is an EDT patch which makes it more ISO-8859-1 friendly, actually 
> prompted by a customer who used EDT for strictly ASCII except for a 
> character at the 'þ' position (but not þ).  

So the patch causes the wanted characters to be displayed?  Of course, 
one can enter any value in EDT.

> EDT fans may want the patch 
> for its ability to understand terminals with more than 24 lines.

Will the patch become standard?  Not that I need a terminal with more 
than 24 lines.  :-)