Patent GB-1071738-A (GB)
Title: Apparatus for the justification of printed text
IPC: G06F40/189
Filed: 1964-08-14
Abstract: 1,071,738. Justification of type. WANG LABORATORIES Inc. Aug. 14, 1964 [Aug. 27, 1963], No. 33182/64. Heading B6W. In an arrangement for producing outgoing coded signals indicative of properly justified text, incoming coded unjustified (or wrongly justified) text is fed to a serial data store (e.g. a stepping register) one stage of which is monitored by a decoder which feeds discriminating circuitry which determines whether justification information may be inserted automatically or not, and in the latter case causes the display of at least some of the stored characters. An operator may then operate manual controls to cause the outgoing text to be justified as he wishes. Normal operation.-Characters in 6-bit code are read by a tape reader 10, Fig. 1, which feeds a two-stage character register 16. This feeds an auxiliary decoder 22 which (a) recognizes case-shift signals and applies case signals to a seventh wire; (b) recognizes signals such as an end of line signal and a hyphen signal before the end of line signal which are deleted by inhibiting the shift control 18 of the text register 20 so that the latter does not accept these signals. The signals thus modified are fed into the shift register 20. At stage 50 of the latter the signals are monitored by a decoder 54 which emits signals on the basis of one wire per character to " justification logic," Fig. 3, where they feed a matrix 112 which emits signals on leads 114 indicative of the width of the character in question. These signals enable gates 120 to emit a number of pulses corresponding to the width of a letter to counters 150. . . 153. Space signals are fed over 116 to gates 121. . . 124 which allot different (decreasing) widths to the spaces and feed counters 150 . . . 153 accordingly. The counters, at any time have thus received pulses indicative of a length of line at present received when different widths for the spaces are used. When each count reaches that corresponding to the length of the line (as indicates over lead 156) they set triggers 172 . . . 175, the last to be set being 175 which corresponds to the smallest space width. As each of the triggers 172 . . . 174 goes over signals are inserted in binary form in combinations of shift registers 162, 164. Moreover, when an interword space is decoded a signal is inserted in shift register 166. These registers together with the marker register are normally shifted at text shift speed to the right, as shown in Fig. 3, or to the left, as shown in Fig. 5. When trigger 175 goes over, it causes the insertion of a marker signal into the marker register 160 which is thereupon shifted by the clock pulse generator 210 at high speed to search for a position at which an interword space coincides with marks in registers 162 and 164, i.e. at a position prior to which counter 152 has been counted out but at which the previous counters 151 and 150 have not. When these conditions are satisfied " and " logic 182 interrupts the rapid scan and the marker 160 then steps at text speed so that the marker signal emerges therefrom synchronously with the end of the word emerging from the text register 20 and this output is used by means, not shown, to cause the insertion of an end of line signal at 72 into the text which then operates a strip perforator 80. Manual operation.-If the above-named conditions are not satisfied, the marking signal emerges on lead 164 and operates the manual intervention flip-flop 216 and prevents further scanning by the marker register 160. Flipflop 216 enables the push-button circuitry 220 relating to the push-buttons 94 and also the gate 222 which can receive over lead 224 a signal from the " interword " push-button 96. The flip-flop also interrupts the normal shifting operation of the text and opens gate 28 to complete a feed-back loop for the text register for enabling the retention of the information in the register in the backwards and forwards shifting thereof that is about to ensue. Thus, the output on lead 218 sets flip-flop 262 which causes the text to be continuously shifted alternately backwards and forwards by equal amounts so as to provide signals for the display device 62. The amount of shift is either 24 characters, or the number of characters necessary to reach the previous interword space, the reciprocation being under the control of flipflop 260 which is changed over when a counter 250 (arranged when it has counted down to 0, to start counting upwards towards 12) reaches 12 or an interword space is detected. The decoder is thus provided with a continuous succession of signals which enable an appropriate number of characters occurring towards the end of the line to be displayed. If the operator decides to hyphenate, he pushes the appropriate button 94 which sets the marker register 202 at a corresponding point. If the line length is justifiable this will be indicated by a signal at the corresponding point in at least one of the justification range registers 162, 164, and a corresponding logic circuit in 184 resets the flip-flop 216. This enables gate 290 so that when the counter 250 next reaches zero flip-flop 262 is restored to disable the display apparatus, leaving the next in its original position in its register. Text shift then occurs as before and when the marker register 160 spills over it signals the code generator to insert the hyphen and end of line signal. If the choice of hyphenation point is such that no corresponding mark is present in either of registers 162, 164 the line is deemed unjustifiable and logic 184 does not emit a signal. After a short delay, circuit 300 initiates stepping of the marker by the 10 kc. clock 210 to clear the mark out of register 160. Moreover, flip-flops 216, 262 remain set to keep the display on. If the operator decides to terminate the line at the last interword space he presses button 96 to open gate 222 to insert a signal in the marker register along which it is then stepped. When the marker signal reaches a position corresponding to an interword signal, then provided there is a signal in registers 162 or 164 at this point indicating that justification is possible logic 184 interrupts the rapid scanning operation and switches-off flip-flop 216 and operations then proceed as in the normal case. If justification is impossible, then the display remains up as before. The operator may over-ride the justification logic by pressing a " bell mode " push-button and terminate the line where he likes with or without a hyphen. The " bell mode " button causes the insertion in the text of a code which causes a bell to ring in the line casting apparatus to inform the operator there that he must effect the justification himself. Deletion.-If a deletion signal is detected at stage 38, flip-flop 310 sets 262 to initiate backward stepping as before. Because gate 284 is closed, the display is not operated and gate 28 remains closed. The backward stepping thus deletes the text, and continues until either an interword space or a count of 12 is reached, after which the stepping is reversed and when the count again reaches zero this restores 262. Preparation for subsequent line.-All the characters to the left of 50 in the text register, at the moment of insertion of the end of line signal, will be required to be recounted afresh for the next line. The end of line signal sets 312 which opens switch 28, inhibits any interword decodings and operates 262 to enable the register shift circuit to move the text back 12 places (or 11 if the twelfth place contains an interword signal), the shift being reversed when the counter has counted 12, so that these characters are now passed to the decoder 54 for re-assessment by the circuit of Fig. 3. Insertion of justification data.-The insertion of the end of line signal may be accompanied by information concerning the width of the spacers to be used in the line as determined by the contents of registers 160, 162, 164. Alternatively, if the shift register is sufficiently long to hold a whole line of text, this information can be inserted with every space signal in the text.