The prior art in this field utilizes flat cables to connect parallel ports at the edge of the board if the array is simple in a manner similar to that used to connect lines similar to those of gaseous display panels, but normally "spaghetti" wiring is used. However, it is known to use long flat cables that can be twisted while the parallel lines of the cable are maintained in parallel. Such flat cables use a connector at the end to connect to connectors at a plug, or they can be soldered to make a connection.
In the prior art, U.S. Pat. No. 4,878,341 granted Apr. 15, 1975 shows a flat straight cable which is twisted to form an interstage linkage for a switching network. This is illustrative of the utilization of straight flat cables for connection. The flat straight cable, shown by U.S. Pat. No. 3,749,959 to Schmersal et al, granted July 31, 1973, and U.S. Pat. No. 3,391,246 to Freeman et al, granted July 2, 1968 has been twisted to form a desired connection. In addition there have been special configurations of clad cables disclosed by U.S. Pat. No. 3,818,122 to Luetzow, granted June 24, 1974 which have a unique configuration which permits opposed end segments of the assembly to be twisted relative to each other so a to achieve a pluraity of independent helices which proved a flexural plane for relative motion between assemblies to which the ends are connected. Dupont (Trademark of E. I. Du Pont de Nemours & Co. (Inc.)) Technical bulletin M-97, Printed Circuits and Flat Cable; June 22, 1970 illustrates a flexible printed circuit and flat cable (like the above patents) on Mylar. There are many other patents which could be cited in the prior art, as this particular art is a field in which such development work has occurred. For instance, U.S. Pat. No. 4,060,889 to Zielinksi, granted Dec. 6, 1977 shows how a flexible electrical circuit connection can be made to gas discharge panels or boards, while U.S. Pat. No. 3,629,787 to Wilson, granted Dec. 21, 1971 shows how they can be connected to each other and to circuit boards. Now the DuPont suggested commercial devices shown by bulletin M-97 do not suggest ground planes or ground conductors, But there are patents like the U.S. Pat. No. 3,039,177 to Burdett, granted June, 1962 and 3,093,805 to Osifchin et al which were then known, and U.S. Pat. No. 4,130,723 to Wakeling, granted Dec. 19, 1978 issued after the bulletin M-97 which show circuit, including multilyaer circuit boards. This latter patent shows the use of signal lines and ground lines or tracks alternating in order and having the opposite face of the circuit having likewise matching alternating ground lines and signal lines, so as to minimize cross talks on data paths. U.S. Pat. No. 3,749,959 previously mentioned shows pairs of flexible straight cables connected to a panel. While not in a flexible cable system, it is also known to plate through holes to interconnect layers of a multilayer device, as illustrated by U.S. Pat. No. 3,895,435 to Turner et al, granted July 22, 1975. In the art of flexible cable U.S. Pat. No. 4,435,614 to McAusland, granted Mar. 6, 1984 and filed Feb. 28, 1983, showed a method of making a long flexible printed circuit board cable by starting with a pattern which has a series of slits separating two parallel cable patterns which are connected to each other by lines which bend by 90 degrees twice to form a U, and the pattern is folded and glued to form an elongated cable having a transducer mount in the center of the cable. German Patent Publication (Deutsche Auslegeschrift) No. 26 22 082 shows a flat ribbon type cable on a plastic foil base being folded with a succession of pleats coinciding with cable run corners to give sideways flexibility and to retain that permanently by heating sealing the fold. U.S. Pat. No. 3,979,763 to Mills, granted Sept. 1976 also shows a flexible circuit and IBM Technical Disclosure Bulletin Vol. 20, No. 8 (1978) shows still another variety of flat printed circuit cable which uses epoxy-glass as a substrate to maintain cross section stability while allowing bending deviation of the cable along its length from a normal stratght line.