To all who may be interested in the 2250 The Wikipedia article is quite short so here it is in its entirety.
<quote> IBM 2250 The IBM 2250 Graphics Display Unit was announced as part of System/360 in 1964. Unlike most modern computer displays, which show images in raster format, the IBM 2250 used vector graphics. A display list of line segments (vectors) on a 1024 by 1024 grid was stored in the computer's memory and repainted on the 2250s CRT up to 40 time per second. Characters were built of line segments specified by display list subroutines. Thus any character set or font could be displayed, although fonts were generally extremely simplified for performance reasons. The computer altered the display by changing the display list. As the display list got longer, the refresh time got longer too and eventually the display would start to flicker. The 2250 was housed in a desk with an alphanumeric (QWERTY) keyboard and a separate programmed function keyboard which had keys, indicator lights and switches. A plastic overlay label could be placed over the function keyboard. Punches on the top edge of the overlay could be sensed by the computer so the keys, lights and switches could be reprogrammed simply by changing overlays. The 2250s CRT measured 21" diagonal, but the useful display area was 12 inch by 12 inch. A light pen was provided as a pointing device, serving the function of the modern computer mouse. An IBM 2285 Display Copier could be attached to the 2250 to provide 8½ by 11 inch hard copy of the display contents under operator control. </quote> http://en.wikipedia.org/wiki/IBM_2250 > ... but I do not remember the size. It covers the key point I wanted to make in connection with this comment. If "size" is a reference to character rows and columns, we are comparing "apples and oranges" as I hope can be noted from the description. ">" ... although fonts were generally extremely simplified for performance reasons. I saw one at one time in use as a console in the Santa Teresa labs - and possibly elsewhere - my memory's not what it was! The "feature" of the presentation of console messages which most impressed was actually the relative crudeness of the character rendering. Incidentally one could suppose that this type of display technology, rendering characters from subroutines of a mathematical nature using lines with start and end coordinates, would find approval from at least one denizen of this list who has gone on record regarding his - for it is a "he" - disgust at the technology of display devices which simply display characters of one font within character cells within the presentation space relative to the beginning of a linear buffer. Chris Mason On Fri, 11 Nov 2011 05:08:28 -0800, Lloyd Fuller <[email protected]> wrote: >There was also a 2250 in that timeframe, but I do not remember the size. We >had >one of each in Stuttgart, but could not use them because the request for the >extra memory to be able to run the communications program was cut from the >budget request. The general did not care about the system memory, just the >CRTs. > >Lloyd > > > >----- Original Message ---- >From: Ed Gould <[email protected]> >To: [email protected] >Sent: Thu, November 10, 2011 8:55:41 PM >Subject: Re: TSO SCREENSIZE > >Rick, > >My memory is iffy here as well but I do remember that we had 12 x 80 screens >but >the model number was 2260. The screen was incredibly small. This was in the >early 1970's. > >Ed ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
