0000000a2a8c2020-dmarc-requ...@listserv.ua.edu (Tom Marchant) writes: > ASCII was seriously considered for the initial System/360 > design. Amdahl, Blaauw and Brooks published an article in the IBM > Journal in April, 1964, titled "Architecture of the System/360" in > which many of the design trade-offs were described. One place where > the article can be found is > http://web.ece.ucdavis.edu/~vojin/CLASSES/EEC272/S2005/Papers/IBM360-Amda= hl_april64.pdf > > <quote> > ASCII vs BCD codes. The selection of the 8-bit character size in 1961 > proved wise by 1963, when the American Standards Association adopted a > 7-bit standard character code for information interchange > (ASCII). This 7-bit code is now under final consideration by the > International Standards Organization for adoption as an international > standards recommendation. The question became =E2=80=9CWhy not adopt ASCI= I as > the only internal code for System/360?=E2=80=99 > > The reasons against such exclusive adoption was the widespread use of > the BCD code derived from and easily translated to the IBM card > code. To facilitate use of both codes, the central processing units > are designed with a high degree of code independence, with generalized > code translation facilities, and with program-selectable BCD or ASCII > modes for code-dependent instructions. Nevertheless, a choice had to > be made for the code-sensitive I/O devices and for programming > support, and the solution was to offer both codes, as a user > option. Systems with either option will, of course, easily read or > write I/O media with the other code. > </quote>
IBMer Bob Bemer ... "father of ASCII" ... EBCDIC and the P-Bit (The Biggest Computer Goof Ever). http://www.bobbemer.com/P-BIT.HTM Who Goofed? The culprit was T. Vincent Learson. The only thing for his defense is that he had no idea of what he had done. It was when he was an IBM Vice President, prior to tenure as Chairman of the Board, those lofty positions where you believe that, if you order it done, it actually will be done. I've mentioned this fiasco elsewhere. Here are some direct extracts: ... snip, see reference for a whole lot more ... have been having problems with outgoing email this weekend, apologize if multiple copies show up -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
