Re: PETSCII mapping?

From: Philippe Verdy <verdy_p_at_wanadoo.fr>
Date: Fri, 7 Apr 2017 04:53:39 +0200

This 2x3 block graphic set was also part of Videotex/Teletext/Antiope
standards in Europe (used on PCs, dedicated terminals, and TV programs, and
still supported in more recent teletext technologies, even if many smart
TVs offer other interactive protocols based on web standards, or possibly
embedding an HTML/CSS/Javascript rendering engine, sometimes even with
Android SDK support for applications). It has even been implemented in some
TV networks in US.
Before graphic displays became widespread (when the EGA standard started
being added, then when non-monochromatic monitors appeared almost
immediately after it), almost all text terminals had such minimal support
for such "mosaic" graphics. Only the original IBM PC had a much more
limited set, using 1x2 blocks, while using box-drawing graphic subset in
their legacy codepages.
The original IBM logo was made of these 1x2 blocks

2017-04-07 3:19 GMT+02:00 Mark E. Shoulson <mark_at_kli.org>:

> On 04/06/2017 08:07 AM, Rebecca T wrote:
>
>> Here’s a copy of the Teletext character set; it includes box-drawing
>> characters
>> for all combinations of a 2×3 grid of cells. 2⁶ = 64 characters, so we
>> might
>> need a new block.
>>
>> [1]: http://www.galax.xyz/TELETEXT/CHARSET.HTM
>>
>> My old TRS-80 also did "graphics" like this, with 64 2×3 cells. That was
> even how it did it when you were setting individual blocks. The smallest
> "pixel" you could control in graphics was one of these ⅙ths of a character
> cell, and wouldn't you know it? As soon as you set one in a cell occupied
> by some other character, the other character would disappear.
>
> Not positive these count as plain text, but there's a decent argument for
> it.
>
> ~mark
>
>
Received on Thu Apr 06 2017 - 21:54:32 CDT

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