Abstract: A data communication system having serial data communication circuits and interrupt data communication circuits and allowing a plurality of CPUs to interchange data with each other. While a pluality of different kinds of data are interchanged by serial communication which occurs at predetermined intervals, only urgent data is interchanged by interrupt signals particular to interrupt communication. Whether or not to validate an interrupt signal (whether or not to mask an interrupt) is determined on the basis of data sent by serial data communication.

Abstract: A flat glass fiber strand comprises a multiplicity of glass filaments having a non-circular cross-sectional shape with the ratio between its maximum and minimum dimensions being between 1.2:1 and 3:1, and which are gathered in such a manner that one dimension of the cross-section of each extends in parallel with the same dimension of the other filaments. This flat glass fiber strand is manufactured by discharging molten glass under high pressure from a multiplicity of nozzles which are shaped in the form of bores having non-circular cross-sectional shape with the ratio between its maximum and minimum dimensions being between 1.5:1 and 6:1 so as to form a multiplicity of filaments of non-circular cross-sectional shape which are then gathered and wound.

Abstract: A method of producing a glass fiber strand in which a plurality of molten glass filaments spun from adjacent nozzle ports in a nozzle plate are adjoined to one another so as to form a single glass fiber having a non-circular cross-sectional shapes such as oval, elliptic, cocoon-shaped and polygonal shapes. The method can employ a nozzle plate provided in the underside thereof with a plurality of recesses in each of which a plurality of nozzle ports are opened, so that the molten glass filaments from these nozzle ports are adjoined to each other so as to form the single glass fiber having a non-circular cross-section.