GB1109342A - Character synthesis arrangement - Google Patents

Abstract

1,109,342. Electric selective signalling. TELETYPE CORPORATION. 21 April, 1966 [21 April, 1965], No. 17470/66. Heading G4H. In printing apparatus in which each character is formed by a sequence of dots an output representing each dot of the sequence is utilized to determine the position of the next dot. In the embodiment described each code input on parallel lines is applied with its complement to two sets of AND gates 83, 84 (Fig. 2) one of the gates in each set being enabled to pass a signal through amplifiers 65, 66 to mark one of the output leads from a diode matrix 15. If however the input represents a machine function, e.g. spacing, line feed, bell or carriage return one of the AND gates 11, (Fig. 3) is enabled to control the printer and also via an OR gate 45 to inhibit a gate 17 and prevent clock pulses from a terminal 13 being applied by a lead 67 (Figs. 2 and 3) to enable the second set of amplifiers 66 and hence disenable the diode matrix 15. Each output lead from the diode matrix threads the cores in a dot core array 16, (Fig. 8) which represent the associated letter. At the beginning of a cycle a reset pulse is applied on wires which thread all possible first cores of a letter the single core which is thus reset inducing pulses on whichever of the wires 92-98, Fig. 8, thread it. The pulses on the wires are applied via shift registers (110, 160, Fig. 4, not shown) to analogue-digital converters (208, 211, 212, 213, Fig. 11, not shown) to control respectively the horizontal and vertical plates of electrodes directing the jet of ink, the binary bits representing the horizontal deflection being preferably temporarily stored in a shift register (200, Fig. 4, not shown) so that the vertical deflection is applied first. The outputs from the second shift register (160) are also applied to two further sets of AND gates (181, 182, Fig. 5, not shown) to mark one output lead from a further diode matrix (21) this output controlling which core in the dot core array (16) should be reset next. All cores which may represent the last dot of a character have a further lead (221, Fig. 4, not shown) threaded through them so that when the last core is reset a spacing pulse is applied to the printer.