Abstract: In a typewriter environment, a carrier mounted sensor for calculating the width of a sheet of paper on the platen and for thereafter setting-up proportional margins for that sheet of paper. In addition to supporting the sensor, the carrier supports the printhead and associated apparatus for detecting the position of the carrier relative to the platen at each escapement position of the carrier. The sensor starts its scan at the extreme left position of the carrier and senses the left edge of the paper at a transition from dark (the platen surface)-to-light (the sheet of paper). This transition point is detected and stored. The carrier continues its rightward scan and the right edge of the sheet of paper signals a transition from light-to-dark. This position is detected and stored. The carrier and sensor continue scanning to the right for a specific distance to eliminate errors that are caused by dark areas on the paper that prematurely trigger light-to-dark transitions.

Abstract: Described herein is a feature and the electronics and logic necessary to implement a paragraph indent feature on an electronic typewriter which is improved and more advantageous than previous routines which accomplished similar results. Paragraph Indent is beneficial to the operator in that it automatically positions the printing carrier at an indented level for setting off typed material so that the left edge of the indented material does not extend to the normal left margin. The typewriter under electronic control stores in memory, upon an appropriate command, a temporary left margin to which the carrier will return when the typewriter is operating under the paragraph indent mode. The operator may enter the Paragraph Indent mode from the keyboard by keying an alternate function or code signal together with a tabulation or tab code signal.

Abstract: On electronic typewriters which have the ability to record into a small working memory those characters, functions and escapements which are keyed at the keyboard, it is many times advantageous to be able to place the carrier and the print point over a character which has been previously typed without using repeated backspaces. Disclosed herein is a feature for an electronic typewriter which permits the operator to easily align the print point with a character on the page by positioning a reference mark on the card holder or print carrier in relation to a previously printed character and then through keyboard control cause the carriage to shift its position such that the print point is then exactly aligned with the character printed.

Abstract: On electronic typewriters which have the ability to record into a small working memory the escapement of the characters which are keyed at the keyboard, it is many times advantageous to be able to reposition the carrier at the rightmost end of the typed material automatically. This is particularly advantageous when it has been necessary to back the carrier up along the printed line for purposes of erasing, correcting or inserting material into that line. Disclosed herein is an electronic typewriter which is controlled by the electronic logic such that the depression of a selected control key will result in the carrier moving from a position within the typed text on a particular line to the right most position the carrier has occupied within that line during earlier typing.

Abstract: An electronic typewriter which has the capability of erasing characters automatically and which has the further improved capability of being able to back through unused space on the line, which results after a tabulation command, thereby allowing the repositioning of the type element over the characters typed prior to the tab command thereby allowing automatic erasure of those characters. The improvement of the typewriter as described permits the retrieving of characters from an electronic memory and the use of that memory to control the erase cycle even where the carrier position and the character to be erased are on opposite sides of space without printed characters due to a tab command. This is accomplished by the electronic control of the mechanical hardware and the ability to determine where the tab command was entered on the typing line and to prevent erasure cycles in the unprinted space until the carrier has returned to the point at which the tabulation command was entered.

Abstract: Disclosed is a method and apparatus for establishing, verifying, and correcting tab settings and indexing parameters for text to be printed by a word processing system. The apparatus includes logic and related control networks for establishing a line of codes in memory indicative of the location and status of such tab settings and indexing parameters, for setting an electronic tab rack, for verifying and correcting such settings and parameters by, and responsive to, the advancement and backspacing of the printer carrier, and for producing a hard copy printout, during entry and playback, of such tab setting and indexing mode status.

Abstract: The aesthetic characteristics of adjacent characters are used to enhance the quality of output in a proportional spacing printer and to provide right margin justification for composing. Spacing between characters is determined on the basis of the character being printed and the preceding character already printed on the page. An intercharacter displacement memory contains a list of ideal spacing for all combinations of characters to be printed. As each character is typed, it and the previously stored preceding character address the intercharacter displacement memory. The output of the intercharacter displacement memory is the ideal value of escapement for this combination of characters and font style. The printer positions the print head prior to printing the next character, rather than positioning the print head after the previous character is printed.

Abstract: Character and control code data are input from a keyboard (12) into a memory (16). A CRT display unit (18) displays one line of data stored in the memory (16). A printer (19) is automatically activated to print the line of data in response to a carriage return or line feed code, a hyphen near the right margin or a space near the right margin with a character in the right margin position. In the latter case, the next line is displayed starting with the character position following the space. The printer (19) prints the line while the next line is being input and displayed. The margins, tab positions and a hot zone near the right margin are displayed above the line of data while a cursor is displayed below the line. Character codes such as backspace codes are displayed with the data and the positions of the data on the display unit (18) always correspond to the printed data positions.

Abstract: A method and apparatus associated with word processing equipment for producing a preliminary printout of accessible lines of intermixed text characters and code characters representative of the format of such text. The apparatus includes logic controlled gates for selectively gating text codes, instruction codes, and reference line number codes to a print control coupled to, and controlling the printing by, a printer. Specific networks enable the printing of "font change" instructions and identifications and characteristic identifier symbols indicative of the presence of an instruction code. Audit print codes representing material ones of the instruction codes are substituted for the usual printer functional response to those instruction codes, that is, a code representation of the instruction code is printed instead of the printer executing the instruction.

Abstract: A control system for high speed printers including a low speed microprocessor that processes data input by a one-time serial operation on the data bytes to direct printing operations into a virtual image memory that is a map of the printing sequence for an entire line. A map of the character printing program for each print position is transferred for each character into a print control memory so that printing can proceed as though a large scale high speed computer was in charge of the printing process.

Abstract: A system having two tab racks for controlling playout of sequentially stored text columns in a side-by-side format. During input keying set up of a job, desired tabs are set in a text tab rack and stored in a text buffer along with the text. These tabs will be in control for following keyed text. If new or additional tabs are required to define column boundaries during later playout, they are keyed, set, and stored prior to the text for the columns. In any event, the tabs in effect at the beginning of input keying of the columnar job will be in control for the column text. Upon later playout from the buffer and when the beginning of the first column is reached, a copy of the tabs set in the text tab rack is transferred to a column tab rack to control the column boundaries. If different tabs are required for the text in the columns, they must have been stored in the buffer after the beginning of the first column or playout must be interrupted for input keying of these tabs.

Abstract: A system for printing a plurality of sequentially stored text columns in a side-by-side format with the line spacing of one column varying from that of another. Each column is to be printed out in an operator defined location. After a line from one of the columns is printed on a print line in a defined location, the carrier is caused to escape. Any corresponding lines from succeeding columns, as determined by their line spacing requirements, are printed on the same line prior to causing a printer carrier return. That is, the line spacing requirement of a column is utilized to determine whether a line from the column is to be printed on the print line being printed.

Abstract: A system for handling multiple printer font requirements during playout of a plurality of sequentially stored text columns in a side-by-side format. A line from one column is printed on a print line, the carrier is caused to escape, and any corresponding line from a succeeding column is printed on the same line. Printing and escapement continue until all corresponding lines from each column are printed on the same print line prior to causing a printer carrier return. During playout within a column, or from column to column, printer font requirements stored with the text are used to determine subsequent system events. If one of the columns, or a portion thereof, is to be printed in a different type style or language, the system will signal a need for a font change, stop the playout and await an indication that a font change has been made.

Abstract: A rotary encoder is coupled to the drive for a printing head to detect and encode movement of the drive and produce signals therefrom which are used to control the direction and positioning of the printing head. A rotating disc-like wheel in the encoder has a plurality of peripheral window openings which act in conjunction with a light source and detector to produce a signal train from which the movement and instantaneous location of the printing head is determined.

Abstract: Three fixed optical sensing devices are positioned to sense the left and right margins as well as the center location of high speed printer carriage travel. Signals from the sensing devices are fed to programmed carriage logic control circuits which effect rapid carriage movements relative to the center location as well as the traditional left and right margin locations. Printing time of certain forms is greatly reduced by minimizing unnecessary carriage return to the left margin location.

Abstract: A panel of selectively-controllable indicator elements is associated with a viewable escapement scale on a typewriter and provides an indication of a set of operative tab stops stored in an electronic memory. Escapement position codes extracted from an electronic tab storage drive a logic circuit that is so connected as to modify the state of individual panel elements at corresponding escapement scale positions to indicate a tab layout. By providing, in a preferred implementation, means for accessing the presently operative (selected) set of tab codes from a memory adapted to retain plural tab sets, the operator is enabled to assess the layout of each selection visually. In such an implementation for a typewriter having two different selectable pitches, say pitches of 10 and 12 characters per inch, the panel elements are arranged to display the selected tab layout respective of pitch.

Abstract: A tabulation control system including a tab position memory shift register for memorizing tab-set position signals representing summed up values from the first position in a range in which tab setting operations are possible. A buffer register is connected to receive tab-set position signals in response to shift signals according to tab commands, a printing head position counter for counting the total and number of shifts of a printing head from the first position is provided. Also provided is coincidence detector which compares the output from the buffer register with the output of the counter and stops the printing head when these outputs coincide with each other.

Abstract: A word processor system comprising a typewriter, a data storage unit, a tab stop register for storing signals representative of tab stops set on the typewriter and means for controlling the tab stop register to keep it aligned with the typewriter carrier during the course of typing including backspacing, carrier return and tabbing actions. Additional means responsive to tab command and tab stop signals is provided for recording a tab action in the data storage unit as a succession of encoded space signals equal to the number of typing positions to the next tab stop from the carrier position at the instant of the tab command.

Abstract: A printer system having local control for dynamically positioning a print head relative to a print medium utilizing positioning and print data signal inputs, including a control unit for receiving and storing data inputs, the control unit including circuit means responsive to the positioning data for arranging and outputing the stored print data to a print head, control circuitry connected to said control unit and head positioning apparatus employing a movable print medium connected to the control circuitry for positioning the head in relationship to the web in response to said control circuitry so that the head is thereby dynamically controlled by the respective data signal inputs.

Abstract: In a serial printer a movable type character element such as a ball, disc or the like is rotated to present different type characters to the print position. The carrier for the type element is moved along the print line at a predetermined maximum velocity so long as it is possible to move the type element to the next character in time required to move the carrier from one print position to the next. If the type character set-up time is greater, the carrier is run at a slower speed and is then returned to the predetermined velocity for printing.