My Vintage Dream PC

Discussion in 'Computer Information' started by GreenXenon, May 18, 2009.

  1. This is a good thing. When was it released?

    -- Patrick
     
    Patrick Scheible, Jun 11, 2009
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  2. GreenXenon

    Joe Pfeiffer Guest

    Most CS departments have an undergrad class in compiler writing, in
    which the term project is to write (for a toy language, of course).
    They don't write it in machine code!
     
    Joe Pfeiffer, Jun 11, 2009
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  3. The bad thing is that it's proprietary storage with no
    available documentation on the storage format (at least there wasn't when I
    used ClearCase). It was also fragile when I used it and hard to set up. It
    may have improved but using it made me think fondly of CVS.
     
    Ahem A Rivet's Shot, Jun 11, 2009
  4. I suspect getting time on one of those 5 computers would be like
    getting observation time on the hubble.

    I should ask around the MV plant and see if there's anyone left that
    remembers.

    scott
     
    Scott Lurndal, Jun 11, 2009
  5. IIRC, 20 years ago. I believe it started on the Apollo systems.

    It would only be a good thing if it were open source, never a good
    idea to trust your crown jewels to a proprietary file(system) format; will
    almost always bite you in the end.

    scott
     
    Scott Lurndal, Jun 11, 2009
  6. Sigh.

    -- Patrick
     
    Patrick Scheible, Jun 11, 2009
  7. GreenXenon

    Mensanator Guest

    I don't know about PDP's, but the minis I built (based on
    GA SPC-16) had 3 backplanes: CPU, I/O, EXPANDED MEMORY.
    When building the complete computer, they would be brought
    up in that order. The bootstrap ROM was part of the EXPANDED
    MEMORY, which required a controller in the I/O backplane.

    The ASR33 was connected directly to the CPU backplane, so I
    spent a good portion of my life toggling in the papertape
    bootstrap loader (6 16-bit words) which I eventually
    memorized. Not because I wanted to, just from having done
    it so often. One day, after leaving that company, I woke
    up and suddenly realized I had forgotten the papertape
    bootstrap!

    What a great feeling, like being released from the French
    Foreign Legion.
     
    Mensanator, Jun 11, 2009
  8. Write a c compiler in c is the basic exercise.
     
    Walter Bushell, Jun 12, 2009
  9. GreenXenon

    Joe Pfeiffer Guest

    That's a bigger exercise than needed to get the point across. When I
    taught the class a couple of times I defined a small subset of C I
    called Cb (pronounced C flat); it wsa written in C, lex, and yacc, and
    generated Motorola HC11 code.
     
    Joe Pfeiffer, Jun 12, 2009
  10. GreenXenon

    FatBytestard Guest

    It cannot be a basic exercise if one is writing in C. Tee hee hee...
     
    FatBytestard, Jun 12, 2009
  11. I "researched" this before and received the following information:

    In "KSNJFL", each letter was represented by the correct decimal value
    in the five-level teletype code that communicated with the computer.
    The computer input was mainly paper tape produced by teletype.

    Charlie Jones of the University of Iowa sent the following to me in
    an email:

    Here is the 5-level code used by Illiac, transcribed from THE ILLIAC
    MINIATURE MANUAL, by John Halton, Digital Computer Laboratory File 260,
    University of Illinois, Urbana, 1958, page 3. I have preserved the
    layout as much as is possible using ASCII:


    THE TAPE CODE
    -------------
    | Characters | n for 92 | Characters | n for 92
    Tape Holes | F/S | L/S | Orders Tape Holes | F/S | L/S | Orders
    ---------------------------------- ----------------------------------

    | o | 0 P 2F |O o | Delay Delay 3F
    | o O| 1 Q 66F |O o O| $(Tab) D 67F
    | o O | 2 W 130F |O o O | CR/LF CR/LF 131F
    | o OO| 3 E 194F |O o OO| ( B 195F
    | oO | 4 R 258F |O oO |L/S=Letter-Shift 259F
    | oO O| 5 T 322F |O oO O| , V 323F
    | oOO | 6 Y 386F |O oOO | ) A 387F
    | oOOO| 7 U 450F |O oOOO| / X 451F
    | Oo | 8 I 514F |OOo | Delay Delay 515F
    | Oo O| 9 O 578F |OOo O| = G 579F
    | Oo O | + K 642F |OOo O | . M 643F
    | Oo OO| - S 706F |OOo OO|F/S=Number-Shift 707F
    | OoO | N N 770F |OOoO | ' H 771F
    | OoO O| J J 834F |OOoO O| : C 835F
    | OoOO | F F 898F |OOoOO | x Z 899F
    | OoOOO| L L 962F |OOoOOO| Space Space 963F
     
    Charles Richmond, Jun 12, 2009
  12. So you just read books, wrote your own compiler, turned it in, and got
    a grade??? *No* one was teaching you any of this???
     
    Charles Richmond, Jun 12, 2009
  13. Isn't it *more* difficult to produce code for the 8-bit HC-11 than
    it would be for the MC68000 ??? The MC68000 has a reasonable assembly
    language/machine language for producing code. You can use actual
    multiply and divide instructions rather than writing your own multiply
    and divide *routines*. (You probably *gave* the students those routines
    to call from the compiler binary output.)

    And how about linkage to functions??? You *did* have functions???
     
    Charles Richmond, Jun 12, 2009
  14. I had a friend who was a grad student. Once he went into the
    department office and asked the secretary for some "dildo paper".
    She just handed him some ditto paper and said nothing.
     
    Charles Richmond, Jun 12, 2009
  15. GreenXenon

    Joe Pfeiffer Guest

    The HC11 has the huge advantage that it's the machine we use in our
    assembly language class (we have them build a SBC and control LEGO
    robots with it), so the students already know it and they know the
    simulator we use for it.

    It's also got multiply and divide instructions. The thing about a toy
    language for a class, though is that if it didn't have them, the
    language could be defined to not have them either (you have to have
    enough operations to exercise operator precedence, but bitwise boolean
    operations would suffice for that).
    It's got push and pop instructions, pushes return addresses on the
    stack, does indexed addressing....
     
    Joe Pfeiffer, Jun 12, 2009
  16. GreenXenon

    Joe Pfeiffer Guest

    Dr. Freud, paging Dr. Freud to the white courtesy phone...
     
    Joe Pfeiffer, Jun 12, 2009
  17. It's still proprietary. There might be some hope that the client side
    will be opened now that IBM owns rational. They would still get the
    money from the server side, and the client-computer support would be
    easier.

    CC is sometimes fragile, it needs administration. But on the other hand
    it supports many features that the others don't. For example the
    building avoidance is a nice feature in big environments i.e. if the
    versioned file is already compiled in someones view it is just copied
    over, not compiled.

    CVS is something I don't like, SVN is CVS with steroids, but still quite
    old fashioned. Especially branching etc. is quite bad in CVS, and was
    quite bad in SVN until recently. But still ClearCase is much better if
    huge amount of branches, labels etc is used. I also like the idea of the
    new distributed VCS systems (git, bitkeeper etc.), they are the future I
    would say. In distributed systems the single points of failure
    are not there, and they scale nicely with the amount of developers.

    --Kim
     
    Kim Enkovaara, Jun 12, 2009
  18. Being fragile was an instant death issue for me - a VCS must not
    lose data *ever*, when I tried it CC lost whole projects.
    Scary - compilation is often sensitive to the environment.
    Yes it is - but then I prefer to keep branching to a minimum and
    use the "develop in head and merge to release branch" approach rather than
    the "develop in a branch and merge to head" which I find to be unmanageable
    no matter what tools are used.
    You may well be right, although AFAIK they all lose the nice
    feature of CVS that the RCS files it uses are readable and easily found. In
    extremis you can even repair an RCS file with vi if you manage to break one
    somehow.
     
    Ahem A Rivet's Shot, Jun 12, 2009
  19. GreenXenon

    jmfbahciv Guest

    This was in the late 60s and the system was an IBM 1620.

    /BAH
     
    jmfbahciv, Jun 12, 2009
  20. GreenXenon

    jmfbahciv Guest

    What books? I don't recall ever seeing a text book.
    Not turned it in. Demo'ed it.
    No grade. The compiler either worked or it didn't. When it worked,
    you got an A.
    I never got to take the class. and there wasn't anybody to
    teach it. The people who did write one learned as they went.
    They knew how a compiler was supposed to work because we had
    FORTRAN II on the system.

    /BAH
     
    jmfbahciv, Jun 12, 2009
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