The 3279 used tri-plane symbols for extended colour (turquoise, pink, yellow and white, plus blank for all 3 primary colours off). This had the neat trick of allowing easy reverse video highlighting (invert the primary colour bits). GDDM was the software exploitation of 3279, which also introduced program symbols. Most programs used 10% of the 3279s rather complex capabilities (a situation not helped by only 2 of the 3279 models having the full capability set). Great case study on how to design great hardware badly, or rather so that it is not used.
Note that the 2260 (3270 predecessor that used a keypunch mechanical keyboard) and 2250 (million dollar vector graphics terminal) were released circa 1965. So the 3279 is 15 years later. On Wed, Feb 24, 2021 at 7:55 PM Martin Packer <martin_pac...@uk.ibm.com> wrote: > The interesting question to me is "which colours"? > > I would say we started with a 3-bit colour space: R, G, B. And so the > colour Red is 100 in this space and a more complex colour like Yellow is > probably 110. > > Is this right, though? > > In particular I'd be surprised if a 4th bit weren't used. But for what? > > Cheers, Martin > > Martin Packer > > WW z/OS Performance, Capacity and Architecture, IBM Technology Sales > > +44-7802-245-584 > > email: martin_pac...@uk.ibm.com > > Twitter / Facebook IDs: MartinPacker > > Blog: https://mainframeperformancetopics.com > > Mainframe, Performance, Topics Podcast Series (With Marna Walle): > https://anchor.fm/marna-walle > > Youtube channel: https://www.youtube.com/channel/UCu_65HaYgksbF6Q8SQ4oOvA > > > > From: Tony Harminc <t...@harminc.net> > To: IBM-MAIN@LISTSERV.UA.EDU > Date: 24/02/2021 01:00 > Subject: [EXTERNAL] Re: Colours on screen (mainframe history > question) > Sent by: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> > > > > On Tue, 23 Feb 2021 at 19:10, Seymour J Metz <sme...@gmu.edu> wrote: > > > IBM had color support for DIDOCS, ISPF and XEDIT pretty early. I don't > recall when GDDM picked up color support. > > Very early 1980s - earlier than I remember support for DIDOCS or ISPF. > And almost certainly GDDM was under development in parallel with the > 3279 hardware; IBM rarely comes out with hardware on a whim that has > no software to support it. One must also remember that the 3279 was > merely the first implementation of an architectural shift in the 3270 > series. > > Tony H. > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > > > > Unless stated otherwise above: > IBM United Kingdom Limited - Registered in England and Wales with number > 741598. > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
