Teletext separated mosaic graphics
kent.b.karlsson at bahnhof.se
Mon Oct 12 17:40:05 CDT 2020
> 8 okt. 2020 kl. 00:25 skrev Harriet Riddle via Unicode <unicode at unicode.org>:
> However: although MARC 21, the standard defining character encodings for Library of Congress records, uses a subset of ISO 6630 with some extensions (in positions not used by ISO 6630) as its C1 set within MARC-8 (its 8-bit, somewhat ECMA-35-based encoding), it however uses ECMA-48 as its C1 within Unicode, which means that it resorts to using SOS and ST instead of NSB and NSE (marking up a range of characters to be ignored during collation but nonetheless displayed).
ECMA-48 on SOS…ST: ”A control string is a string of bit combinations which may occur in the data stream as a logical entity for control purposes.”
What is implicit there, and not sufficiently clearly stated, is that the control string as such is not supposed to be displayed. It may be commands that do something, but is not intended to be text to be displayed as-is.
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