Abstract: A printed circuit board having resistors formed therein. A conductive layer composed of two different metals is provided on top of an insulating layer in a printed circuit board. The first metal layer is highly conductive and the second metal layer is highly resistive. For a major portion of the layer, both layers are connected electrically in parallel so that they provide a highly conductive path. At selected locations throughout the printed circuit board, the highly conductive metal is removed providing only the high resistivity metal to act as a resistor between selected locations in the conductive layer. Many resistors are formed at the same time, thus providing ease of fabrication and precision in resistor values across the entire printed circuit board. Following the formation of the resistor, additional insulating and conductive layers are formed to complete the printed circuit board.

Abstract: A device and method for initializing the state of a computer, including individual transmission lines within the computer. A signal sending circuit provides an output signal onto a transmission line. While the signal is propagated along the transmission line, a second signal is provided in series on the same transmission line. Simultaneously therewith, the value of the first signal is stored in a data storage element. Subsequent bits may be placed on the transmission line before the first bit is received at a second end of the transmission line. Each bit placed on the transmission line is stored in a respective data storage element. The value of the data in the data storage elements can be tested to determine the exact state of any transmission line in the system.

Abstract: A printed circuit board having resistors formed therein. A conductive layer composed of two different metals is provided on top of an insulating layer in a printed circuit board. The first metal layer is highly conductive and the second metal layer is highly resistive. For a major portion of the layer, both layers are connected electrically in parallel so that they provide a highly conductive path. At selected locations throughout the printed circuit board, the highly conductive metal is removed providing only the high resistivity metal to act as a resistor between selected locations in the conductive layer. Many resistors are formed at the same time, thus providing ease of fabrication and precision in resistor values across the entire printed circuit board. Following the formation of the resistor, additional insulating and conductive layers are formed to complete the printed circuit board.

Abstract: A printed circuit board having resistors formed therein. A conductive layer composed of two different metals is provided on top of an insulating layer in a printed circuit board. The first metal layer is highly conductive and the second metal layer is highly resistive. For a major portion of the layer, both layers are connected electrically in parallel so that they provide a highly conductive path. At selected locations throughout the printed circuit board, the highly conductive metal is removed providing only the high resistivity metal to act as a resistor between selected locations in the conductive layer. Many resistors are formed at the same time, thus providing ease of fabrication and precision in resistor values across the entire printed circuit board. Following the formation of the resistor, additional insulating and conductive layers are formed to complete the printed circuit board.

Abstract: A circuit and method for replacing a defective memory line with a usable memory line. A test is carried out to locate any defective lines, whether a row line or a column line, within a block of memory. If a defective line is found, the identity of the defective line is stored in software code. The software code is stored in a file or table, or other acceptable location, together with the identification of the memory block which is associated with the test data. When the computer is enabled for operation, the test data is loaded from the file into a register associated with the memory. When the memory is addressed, the register prevents addressing to the defective memory line and replaces it instead with an alternative line in the memory which has been tested as usable for storing and retrieving data.