Article 3905 of alt.sys.pdp10: Path: nntp1.ba.best.com!news1.best.com!nntprelay.mathworks.com!howland.erols.net!newsxfer.itd.umich.edu!uunet!in1.uu.net!bulb.garlic.com!not-for-mail From: Anne & Lynn Wheeler Newsgroups: alt.folklore.computers,alt.sys.pdp10 Subject: Re: ** Old Vintage Operating Systems ** Date: 25 Apr 1998 14:37:43 -0700 Organization: South Valley Internet Lines: 28 Message-ID: References: <6gg7k$3e3@news-central.tiac.net> Reply-To: Anne & Lynn Wheeler NNTP-Posting-Host: lynn-18.garlic.com X-Newsreader: Gnus v5.6.4/Emacs 19.34 Xref: nntp1.ba.best.com alt.folklore.computers:102923 alt.sys.pdp10:3905 my first experience was with monitor was 1401 MPIO (i believe stood for multiprogram input/output) ... it was card deck that booted into 1401 and handled the unit record spooling for 709 ibsys (card->tape, tape->printer/punch); i.e. 709 ibsys ran fortan jobs tape<->tape. summer job i got as undergraduate (after taking a 2hr semester intro to programming class) was to recreate the 1401 MPIO monitor on 360/30 ... so the 2540/1403 unit record gear could be switched to the 30 ... and the 30 could be used for both 360 testing and still provide front-end functions for the 709. i designed and implemented my own interrupt handler, device drivers, i/o supervisor, multi-tasking supervisor, error recovery, operator interface, memory manager, etc. ,,, it had to support all of the 1401 MPIO functions ... including being able to distinquish between bcd/ecbdic and column binary cards (i.e. had to seperately feed & read ... since if not bcd ... would have to reread in column binary) ... was able to concurrently overlap card->tape and tape->print/punch using dynamic buffering of all available memory on the 30. i used a BPS loader to read monitor into 360/30 and take over all functions of the machine. when MPIO wasn't running ... 360/30 booted OS and was used for OS testing (and/or recompiling my program). -- Anne & Lynn Wheeler | lynn@garlic.com, finger for pgp key http://www.garlic.com/~lynn/