I had to install a hardware switch on the bottom of my Radio Shack TRS-80 Model I in 1979 to write my first book in mixed case, and only one EDITOR program would display lower case - I could not read system messages when the switch was LOW.
Barry Merrill -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Joel C. Ewing Sent: Monday, February 18, 2013 10:22 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Dualcase vs monocase. Was: Article for the boss... On 02/18/2013 05:36 AM, Shmuel Metz (Seymour J.) wrote: > In <201302151911.49741.jlturr...@centurytel.net>, on 02/15/2013 > at 07:11 PM, Leslie Turriff <jlturr...@centurytel.net> said: > >> Not so much a mistake as short-sightedness; before 3270s were >> available, keypunches could only do upper-case > In the same time frame IBM had software that supported dual case > using, e.g., 1050, 2740, 2741. I suspect that moncase had more to do > with corporate culture than hardware. > Having a few devices that supported dual case didn't necessarily make it economically reasonable to adopt dual case. There was considerable (more than a decade) overlap between use of card equipment and the deployment of 3270 devices, and as already remarked, card punches didn't support dual case, nor did the original 3277 model of 3270 in 1971. It took another 8 or 9 years after introduction of the 3277 before the first 3278 terminals with full dual case support became available and much longer before all 3277's were phased out. There was a strong economic motivation for the lowest common capability to determine local standards. Our data center didn't totally phase out the use of cards until sometime after 1985, after conversion to MVS, and line printers with higher dual-case costs persisted for decades after that. I'm not sure how early one could get dual case support for line printers, but the most common high-speed production print technology pretty much through the end of the 20th century were line printers with print bands or print trains, and using dual-case bands or trains reduced the number of repeated patterns and effectively cut print speed in half, doubling the hardware cost of printing dual case. Laser printers like the IBM 3800 which didn't have this problem were available from the late 1970's, but they were very expensive and supported the print volume of 5-10 line printers -- you had to have an incredibly high print volume or an application that absolutely demanded that print flexibility to cost justify two of them (so you could continue production when one was down for extended maintenance). Now that relatively cheap slower laser printers with multi-font support are ubiquitous, print band line printers are on the decline, application development and data entry are no longer tied to punched cards, and mono-case display terminals are long gone, dual-case support is almost no-cost. That was not the case for decades, and corporate culture (in the companies that are still in business) did tend to frown on expenditures that were deemed avoidable and which could not be cost justified. Existence of millions of lines of program source written with mono-case conventions may continue to influence local coding standards, but at least the hardware cost penalty of dual case is no longer an overriding factor. Many of the early choices in computing which don't make sense to the latest generation were simply driven by the economic realities of the time. -- Joel C. Ewing, Bentonville, AR jcew...@acm.org ---------------------------------------------------------------------- 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
