Questions regarding HP Roman character set

[matthiaspaul]

Hi,

I recently wrote an article about the "HP Roman" character set, its history, its properties, the variants in existance, and how they are (or were) used in their various environments:

HP Roman

While the article covers the main aspects already, there are still quite a few details I would like to see included for completeness and accurateness. As some of you are much more familiar with the history of Hewlett-Packard and their products, I guess, some of you could provide valuable information.

Here's the short list of remaining open questions:

- When exactly was "HP Roman Extension" introduced? The earliest documents using this name I could find are dated 1979, but the machines they describe (HP 300 and HP 250) seem to have been announced or even have been available in 1978 already. Before that date, I could find references to "extended international character sets" etc., but from the very incomplete info I found about them, they seem to have had no similarity with "HP Roman Extension" (different characters, different codepoints). Anyone?

- The earliest character map for "HP Roman Extension" I could find dates from 1982 (but this does not mean, that this particular definition wasn't used earlier already), and it still had many codepoints undefined. When was the 1982 definition actually introduced? Does someone know even earlier representations? Which characters were lacking?

- I have found some hints that a HP document named "2640 Series Character Set Generation 13245-90001" might contain character maps of an earlier revision of "HP Roman Extension", but it also could be for another character set, given that the document is apparently dated 1975 (this would precede the earliest date I could find for "HP Roman Extension" by four years). So far, I was unable to find this document. Does someone own a copy of it?

- I found 1984 definitions of both, "HP Roman Extension" and "HP Roman-8", which still had 6(+2) characters undefined. This changed with the 1985 revision of "HP Roman Extension" and "HP Roman-8", which added 6 characters and changed the definition of one character (228) from a stroked d to an eth. These 1985 definitions are also in line with what IBM standardized as codepages 1050 and 1051 in 1989, and except for the "modified HP Roman-8" variant used on early HP RPL calculators in 1986-1988, I am not aware of any other changes later on (except for inofficial "euro" extensions and the later "HP Roman-9"). Are you aware of any revisions of "HP Roman Extension" or "HP Roman-8" after 1985? The pattern of undefined characters before the 1985 revision looks a bit strange to me (two groups 177-178 and 242-245) - why were these areas left undefined in the middle of the code space? (Well, this question applies even more so to the 1982 definition, which left many holes of definition instead of filling up the character set from the bottom more orderly. I assume that this might be down to internal negotiations and back&forth changes - perhaps there is interesting history to be told here as well?)

- Regarding the 1984 definition of "HP Roman-8", it is my assumption that it is the same as the original(?) 1983 definition of "HP Roman-8", right? Or have there been earlier variants with more characters lacking or different before 1984?

- Regarding the 1984 definition of "HP Roman Extension", it obviously differs from the definition in 1982 (which, however, might have been introduced earlier). Is it safe to assume, that there was a 1983 revision, which introduced "HP Roman-8" and brought "HP Roman Extension" to the same level?

- When exactly was the name "HP Roman-8" introduced? The earliest reference using this name I could find was in 1983, but there might have been earlier sources. Before 1983, I only found references to the 7-bit and 8-bit "HP Roman Extension" character set, kind of a pre-cursor.

- When exactly was HP Roman-9 introduced? I could find documents in 2001 which imply that some of the earliest printers to support it were produced in 1998, but I could not find any kind of announcement, so I stated "around 1999".

- Regarding the modified HP Roman-8 character set used on early HP RPL calculators like the HP-28C/HP-28S (and the HP-18C) and the HP 82240A printer, does someone know an official name for that variant? Some of the added characters are very odd, others duplicate already existing characters. There certainly is some history to this particular extension. Why were these characters chosen, when exactly and by whom? Which other calculators used this character set? Were there other printers but the HP 82240A/B to use this? AFAIK the HP-28 could only display characters up to 147, probably because of limited ROM space, but why did it duplicate the guillemets at 146/147 (or are they different from 251/253), and what is the purpose of the "LF" character at 144? Why did the printers support such a large number of strange superscript and subscript indices? And what is the purpose of this strange graphical symbol at 148?

- Are there any official mappings from HP Roman-8 to Unicode? Or does someone have an overview of the different mappings introduced in HP and third-party software products (including emulators)? If possible I would like to document the specific differences.

Thanks and greetings,

Matthias