Abstract: Binary coded address information is written by a magnetic head on a magnetic recording medium, such as a disc, as a plurality of tracks, each having an address associated with it. Each track includes a reference zone containing a plurality of individual cells equal to the number of bits in the address. Each cell represents a binary value and includes two binary state transitions, each of which can occur at one of only two positions. One transition of each cell in each zone occurs at the same position within the cell, with adjacent zones having alternating positions of this transition. The other transition in the cells in each zone occurs at either position to represent the binary values.

Abstract: A peripheral controller capable of simultaneously handling data transfer microprocesses for several different peripheral devices. The controller includes a set of memories, logic circuits and a physical interface channel for transmitting data between a control processing unit and the peripheral controller and for transmitting data between the peripheral controller and the peripheral devices, an interface control unit for enabling a predetermined one of the peripheral devices to communicate with the peripheral controller, a memory for storing microprograms for controlling the data flow between the control processing unit and the peripheral devices, and a processing circuit for administering the sharing of the processing time of the peripheral controller between the plurality of peripheral devices and the control processing unit.

Abstract: Temperatures are automatically measured with a Wheatstone bridge including first and second branches and a diagonal connected between taps of the branches. The first branch includes first and second series connected resistors respectively having values of P and Q; the second branch includes third and fourth series connected resistors respectively having values of R and A. A voltage source, having a value E, is connected to energize the branches in parallel. The third resistor is temperature responsive and has a positive temperature coefficient so that the value of R is given by:R = R.sub.0 (1 + .alpha..sub.0 T)whereinR.sub.0 = the resistance value of the third resistor at 0.degree. C,.alpha..sub.0 = the temperature coefficient of the third resistor, andT = temperature in degrees Centigrade.

Abstract: A system for recognizing printed characters each composed of a predetermined number of vertical lines arranged in accordance with a given code wherein the characters are read serially as a result of the document being moved between an input station and an output station of a transport mechanism associated with a reading device. The reading device includes at least one amplitude discriminating circuit having various threshold levels applied to it. Means are provided for locating the point at which the reading of the document commences and for reading the document and generating a read signal during the whole period when the document is being read. A buffer store is connected to the reading means for temporarily storing read characters which are satisfactory for use. Repeat reading means are connected to means for reading the document and to the buffer store.

Abstract: A ribbon driving and tensioning apparatus includes a pair of identical mechanical assemblies connected to reversibly drive associated rollers which support a printing ribbon. Each assembly includes a bi-directional DC reduction motor the output shaft of which is connected through a friction clutch assembly to the supporting shaft of a roller. The roller shaft includes a brake for applying a resisting torque in a direction opposite to that of the shaft rotation. A switching assembly for reversing the current to the motors and thereby reverse the direction of drive of the motors includes a pair of reversing switches mechanically coupled to a lever adapted to be pivoted between a first and a second position by a strip actuator positioned on the ribbon. A strip actuator is positioned adjacent opposite ends of the ribbon such that the direction of travel of the ribbon is reversed when the ribbon is almost completely unwound from one of the rollers.

Abstract: A container for a magnetic data recording disc includes a flat cassette shaped for insertion into a receptacle of disc memory of a data processing apparatus. A normally closed opening in a sidewall of the cassette provides access to the disc for recording and/or reading heads of the data processing apparatus. The cassette includes a pair of generally parallel walls that extend in a direction generally parallel to faces of the disc. One of the opposing walls includes an opening for enabling rotary drive means of the apparatus to be coupled to an annular hub of the disc. The opposed walls are rigid, but elastically deformable. In a free state, the opposed walls are outwardly convex. An internal projection extends from the center of the other opposed wall. The projection has an annular bearing surface facing the inside face of the other wall. The one opposing wall has an opening coaxial with the projection. The opening is surrounded by an annular bearing surface on the outside face of the one wall.