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bus and "flip-chip" style cards
bus and "flip-chip" style cards

bus and "flip-chip" style cards

Date1960-1970
Inventory Number1998-1-0230
ClassificationComputer Element
Subject
    Cultural Region
      Place of Origin
        Place of Use
          Dimensions16.8 x 41.9 x 5.6 cm (6 5/8 x 16 1/2 x 2 3/16 in.)
          Material
            Accessoriescircuit board, "flip chip" cards (10)
            DescriptionThe main body of the bus is a rectangular metal table with four round peg legs. In between each pair of legs on the short end of the table is a cylindrical tube that may be used to screw the bus onto another components or surface.

            The top panel of the table is divided into six sections, each covered by a black plastic plate. Each plate has four connection jacks cut into the surface, each parallel to the long edges of the bus. Underneath the table, each hole in each jack connects to a round metal pin. As such, six rectangular grids of connection pins protrude from the bottom of the bus. Certain of these grids are connected to one another by red and blue wires.

            The bus is accompanied by ten circuit board "flip chip" style cards that fit into the connection jacks on the surface of the table. Each of the cards has a row of thin brass plates at one end, each perpendicular to one edge of the card. This end of each card fits into the connection jacks on the surface of the table such that the brass plates connected with the metal pins underneath. Eight of the cards are the appropriate width to fit into one jack. Two of the cards are twice this size, and they fit into two adjacent jacks.

            At the opposite end to the brass plates on each card is a rectangular plastic sheath and a plastic Y-shaped extension. Six of the thinner cards have beige plastic end pieces. The remaining two thinner cards have black plastic end pieces. Both of the doubly wide cards have two green end pieces. At each end of each plastic end piece is a small hole framed with a metal rivet.

            The main body of each card, in between the brass plates and the plastic end piece, is constituted of a printed circuit board. Various circuit components -- resistors, microchips, capacitors, etc. (click here for a listing of various circuit components and their purposes) are attached to one side of the circuit boards. These pieces are connected to one another, to the brass plates at the bottom by soldered connections and circuits on the other side of each card.

            When the bus is standing on its four legs, the cards stand vertically tall. When the bus is on its side, as it may be when connected to other computer components, the cards do not touch each other, but are stacked horizontally.
            Signedembossed on the plastic end piece of each card: DIGITAL EQUIPMENT CORPORATION / MAYNARD, MASSACHUSETTS printed in blue and white on a blue and white label on edge of bus: digital / EQUIPMENT / CORPORATION / WESTMINSTER / MASSACHUSETTS
            Inscribedtyped and handwritten on a white label on side of bus: Type: M M II S / LOT NO. 08816 embossed on metal plate on side of bus: MM II S / 5964
            FunctionAn early 'Q' bus and circuit cards from the Aiken Computation Laboratory at Harvard University.

            A bus is a mechanism for communicating information between components of a computer or between computers. This bus is a parallel electric bus with twenty-four card connection ports. A comprehensive discussion of computer buses, their history and functioning is available here.

            The twelve cards inserted into the bus are flip-chip style cards. "Flip chip" refers to the style of the circuit connection and soldering that sits on top of the circuit board. It is a space economical development upon standard circuits. These are used to communicate information between computer components. When attached to the bus, these cards can sometimes communicate with each other, or directly with outside mechanisms. A comprehensive discussion of "flip chip" circuitry is available here.
            ProvenanceThis bus and accompanying cards were found in the Aiken Computation Laboratory at Harvard University in 1995.
            Historical Attributes
            internal bus connector
            Digital Equipment Corporation
            Date: circa 1978
            Object number: 1998-1-0582
            internal bus connector
            Digital Equipment Corporation
            Date: circa 1978
            Object number: 1998-1-0581
            Honeywell computer front panel
            Honeywell
            Date: 1960-1980
            Object number: 1998-1-0579
            hard disk unit
            Western Digital Corporation
            Date: circa 1990
            Object number: 1998-1-0593
            Panelvision MiniGraphic "active matrix" display
            Panelvision Corporation
            Date: 1984
            Accessories: single-board display controller cable for display (1997-1-0686c) shipping ticket/ hand carry pass dated June 11, 1997 (in instrument file) letter to Dr. Richard V. Kollarits from William Andrewes dated June 16, 1997 regarding donation of MiniGraphic display and letter to William Andrewes from Dr. Richard V. Kollarits that accompanied the object upon donation on June 11, 1997 (in instrument file) four sample color prints made with this display on micro-encapsulated photographic paper. 1. man in business suit, 2. woman crouching next to lawn ornament, 3. two clowns painting a third's face, 4. woman in winter hat and scarf (in instrument file) copies of two articles by AT&T Bell Laboratories staff (Richard V. Kollarits, William, H. Ninke, David C. Gibbon) on color imaging and printing (in instrument file) Panelvision pamphlet introducing the MiniGraphic multipurpose flat panel display, including instrument specifications, consumer prices, functioning and features (in instrument file) 1984 article by Panelvision employees (Peter Brody Fang-Chen Luo, Paul Malmberg) on active matrix technology (in instrument file) Panelvision Corporation Fact Sheet, including details of company history and recent developments (in instrument file) article about commercial debut of active matrix technology from Design Engineering newspaper, June 18, 1984 (in instrument file) full circuit diagram and schematic for MiniGraphic Display Controller (in instrument file) instruction manual and description of MiniGraphic Display Controller (two copies, in instrument file) circuit diagrams and instruction manuals for the MiniGraphic Display (two booklets, in instrument file)
            Object number: 1997-1-0686a
            single inline memory modules, SIMMs (3)
            Texas Instruments Incorporated
            Date: circa 1985
            Object number: 1998-1-0576
            core memory module, planar
            American
            Date: circa 1970
            Accessories: with watchglass
            Object number: 1998-1-0577
            control console from Harvard Cyclotron Laboratory
            Harvard Cyclotron Laboratory
            Date: 1947-2002
            Object number: 2003-1-0291
            GIGI graphic terminal
            Digital Equipment Corporation
            Date: 1980
            Object number: 1998-1-0599
            Wang 360SE electronic calculator system
            Wang Laboratories, Inc.
            Date: 1970
            Accessories: cloth instrument cover lined with tissue paper; black power cord; accompanied by central electronic unit (2001-1-003b); two page hand-written note from Peter L. Smith, Research associate, Harvard College Observatory, regarding the donation of the calculator, dated 10 December, 2001 (original and copy in instrument file); photocopy of operation instructions from the bottom panel of calculator unit (in instrument file); printed document on the history of the Wang 360SE by Rick Bensene (in instrument file); printed document on the history of the Want 360SE from Geocity (in instrument file); printed document on the Orbiting Solar Observatories (in instrument file)
            Object number: 2001-1-0033a
            line driver unit (8-Port RS232)
            Jose Lorbes
            Date: 1983
            Object number: 1998-1-0596