Path: csiph.com!weretis.net!feeder6.news.weretis.net!feeder8.news.weretis.net!eternal-september.org!reader01.eternal-september.org!.POSTED!not-for-mail From: Anne & Lynn Wheeler Newsgroups: alt.folklore.computers Subject: Re: Byte Date: Mon, 14 Nov 2022 09:01:19 -1000 Organization: Wheeler&Wheeler Lines: 47 Message-ID: <87zgcttl6o.fsf@localhost> References: <945512337.689781459.530760.peter_flass-yahoo.com@news.eternal-september.org> <8c501639-11e3-4c26-8da4-28811512b2a5n@googlegroups.com> <1160790306.689879393.772545.peter_flass-yahoo.com@news.eternal-september.org> MIME-Version: 1.0 Content-Type: text/plain Injection-Info: reader01.eternal-september.org; posting-host="79b7da2a7965e6e94afdd1e4ee9145f3"; logging-data="1923083"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19xWkY9qFQ/X16QIMfaNL/0hHHw8tStCdE=" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.1 (gnu/linux) Cancel-Lock: sha1:MkDPP3f584szt93tN8y8ncPYL6M= sha1:b9FysMva6M3J/cLEd4w8Tf2LTHk= Xref: csiph.com alt.folklore.computers:222643 Fred Weigel writes: > 12 bits b/c a card has 12 punch rows pre-360, bcd was alphanumerica, small subset of 12 punch row combination. compatibility with pre-360 cards was "column binary" ... two six-bit "bytes" per column. read/write on 360 ... would (column binary) i/o card with 160 length ... two 360 bytes per column (using just 6bits/byte). univ. had 709 tape->tape with 1401 "unit record" front-end running MPIO (tape->printer/punch, card read->tape). They were sold a 360/67 for TSS/360, replacing 709/1401. Temporarily pending arrival of 360/67, the 1401 was replaced with 360/30 (which had 1401 emulation mode). I had just taken two credit hr intro to fortran/computers and at the end of the semester I was hired to rewrite 1401 MPIO in 360 assembler (running 360/30 as 360 instead of as 1401). The univ. shutdown the datacenter on weekends and they gave me bunch of software & hardware manuals and I would have the datacenter all to myself over the weekends (although 48hrs w/o sleep made monday classes hard). I got to design & implement my own monitor, device drivers, interrupt handlers, error recovery, storage management, etc. Within a few weeks had 2000 card 360 assembler program. Later, I assumed it was just exercise in somebody learning 360 (since 1401 MPIO ran just fine on 360/30 in 1401 emulation). Within year of taking intro class, 360/67 came in (replacing 709 & 360/30), TSS/360 never came into production, and I was hired fulltime responsible for OS/360 (and continued to have my dedicated weekend 48hr datacenter time). 2540 reader/punch https://en.wikipedia.org/wiki/IBM_2540 2540 trivia: univ. class registration was card based. 2540 had five output stackers, two dedicated for reader, two dedicated for punch and middle stacker could feed from both reader and punch. program processing cards would read into middle stacker. punch feed was was loaded with colored striped cards ... if a problem was found with registration card, a blank card would be "punched" into middle stacker behind problem card. There was more than a dozen card trays (2000+ cards/tray). After run would pull each registration card that had a blank colored card behind it (for further processing). -- virtualization experience starting Jan1968, online at home since Mar1970