Robert G. Brown
Wed, 23 Jul 2008 20:30:24 -0700
On Wed, 23 Jul 2008, Bob Drzyzgula wrote:
Although it wasn't my first machine [1], I did work with an admittedly-old-at-the-time PDP-8 for a while in the early 1980s. It was used to run a Perkin-Elmer microdensitometer (think quarter-million-dollar film scanner). IIRC it had no non-volatile memory, and thus one needed to hand-load the bootstrap program using the front panel switches [2]. With the one I worked on, there was a hand-written sequence of octal codes taped up on the machine rack, and to fire it up you would mount a certain 9-track tape in the drive, toggle [3] the bootstrap code into memory using switches, and start it to running. The toggled-in code would load the rest of the OS from the tape drive. There was another version that would load the OS from a paper tape reader attached to the teletype, but no one ever bothered with it because it was such a PITA to use. Once you got it going it would read the data from the microdensitometer and write it to another 9-track tape (same drive, you'd unload the OS tape and mount the data tape). And once you had the data tape, you'd take it over to a PDP-11 and process the image using routines coded in Forth...
That's how I booted the PDP-1, almost exactly. Good memory. Except it had the boot program on a paper loop that was permanently installed. Toggle, fire, paper loop goes swoosh, tape drive lives, boot continues.
Anyway, this is a good example of the sort of expectation management that many of us went through in those early days. By comparison, even ed starts to look pretty darned functional. Did I ever mention the months of my life I lost to an attempt to get TeX to (a) compile and run in TSO on OS/MVS, and (b) get it to generate output for an IBM 3820 remote SNA-attached laser printer?
Sounds fascinating;-)
I suppose the bright side, we didn't have to trouble ourselves with firewalls, encryption, virus scanners, security patches, or in many cases even authentication systems...vi back then was little more than a shell on ed IIRCIt was (for nvi, is) the visual mode of ex, which is/was an extended line editor in the lineage of ed, kind of an extended ed.Correct. In ex you would enter the command "vi" at the colon-prompt to enter visual mode. You should still be able to do this on any system with vi installed -- give it a try! :-) FWIW, the shell command "vi" simply fires up ex in that mode to start with.
Fires or fired -- I have no idea what vim does now. I'd have thought that it long ago divorced itself from ed (or em, en, ... ex) at the source level. But I used that trick (hopping from ed/ex into and out of vi) fewer times than I have fingers on one hand back in the day. Why, if one had fullscreen, would one ever use single line? Unless, of course, one was working on a genuine tty lineprinter, which I exceedingly rarely had to do (gnashing teeth most of the time) because the console had crashed somehow and yes, we had a teletype console to log all the messages. Just from working on PC's for five years before starting on Unix, I had higher expectations than ed if there was anything BUT a teletype -- anything with an actual screen. Ed reminded me of edlin, and edlin was a pretty pitiful editor (probably derived in some way from ed, come to think of it). As in one could write a better editor for any PC in maybe 500 lines of basica, and a WAY better editor with any compiler (and still have it fit on a floppy, or at most two). sed, on the other hand, I still use quite regularly, and it is basically an ed extension as well. Being scriptable and grokking regex's makes all the difference in the world, and if you have to change frog to toad in an entire directory of files or manage any number of other clever global changes, sed is hard to beat. Again an arcane tool and not for the timid (and more than a bit dangerous in terms of side effects:-) but if you ask your average a Windows MCSE to go through a directory tree and change all those frogs into toads (or perhaps princes:-) either he'll still be working a week later with some of the frogs turned into prinecs or pirnces or he'll have installed cygwin and done it using sed in less than an hour INCLUDING the cygwin download and install. rgb
--Bob [1] that was an IBM 1130 which bootsrapped off a single, 80-column puchcard containing a small amount of object code. [2] http://en.wikipedia.org/wiki/Image:Multiplex-80_after_30_years.jpg [3] You would enter the address you wanted to start at in octal (actually just binary grouped into three digits) using the switches -- IIRC up for "1" and down for "0", and then throw another switch that would load that number into the address register. Then you'd reset the switches to the pattern for the data you wanted there, and throw the "deposit" switch. Again IIRC as long as you were loading data into sequential addresses, it would auto-increment the address register, so from then on you needed only to keep entering each data value and pressing the deposit switch. And as long as I'm blathering about toggling things in from the front panel, I will go ahead and mention that I'm just old enough to have once been invited over to the home of one of my college professors to see this new Altair 8800 thing he was putting together...
-- Robert G. Brown Phone(cell): 1-919-280-8443 Duke University Physics Dept, Box 90305 Durham, N.C. 27708-0305 Web: http://www.phy.duke.edu/~rgb Book of Lilith Website: http://www.phy.duke.edu/~rgb/Lilith/Lilith.php Lulu Bookstore: http://stores.lulu.com/store.php?fAcctID=877977 _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf