GB898858A - Pulse counter apparatus - Google Patents

Abstract

898,858. Electronic counting-apparatus. WESTINGHOUSE ELECTRIC CORPORATION. July 6, 1960 [July 13, 1959], No. 23615/60. Class 106 (1). In a ring counter each stage comprises two " nor " gates connected together so that when the first " nor " gate has a one output, the second has a zero output, the stages being interconnected by control gates adapted to transfer information when opened. As described, a pulse source 10 supplies a terminal 14 of a bi-stable driver unit 16 comprising " nor " gates 18, 20 adapted to supply output pulses alternately to lines 22, 24. Each stage of the ring counter comprises " nor " gates such as 34, 36, the output of the gate 34 being connected to the input of the gate 36 and the output of the gate 36 being connected to the input of the gate 34. Further inputs to the gate 34 are from a control gate 30 and a reset terminal 62, and further inputs to the gate 36 are from the corresponding gate 44 in the next stage and from a reset terminal 60. The output from the gate 34 is also fed to a control gate 38 having further inputs from a terminal 40 and from the line 24. An output is taken from the output of the gate 38 at a terminal 52. The counter has an even number of stages and the gates 30, 38 &c. are connected alternately to the lines 22, 24. In operation, an initial reset pulse is applied to terminals 15, 58, 60, 64, 68, &c., to set the driver unit 16 to its initial state, the stage comprising gates 26, 28 to the one condition and the remaining stages to the zero condition. When the next input pulse is supplied from the source 10, the driver unit 16 is changed over to cause the line 22 to go to zero potential thus opening the gate 30 to provide an output to the gate 34. The gate 34 is thus switched to provide no output to cause the gate 36 to provide an output. The one state has thus been transferred to the stage comprising gates 34, 36. In this manner the one state is stepped round the ring. In an application, Fig. 2 (not shown), the counter is employed as a distributer to serialize binary information on a plurality of parallel lines, the number of ones being counted on a single-stage binary counter which lights one of two output lamps to provide a parity check for data read from a punched card.