Destination-referenced tab, operations for typewriters that store text

摘要

Tab codes produced at a typewriter keyboard are converted to a form for text storage that includes travel distance and destination information. By using a multiple section code with distinct tab code identifier bytes on either end, the overall tab code can be embedded with normal single byte character codes in a text string and processed specially during forward or reverse operations with storage. For forward operation on a text string, coded destination information is extracted from a preselected byte of the multisection code, upon detecting the tab identifier, and special logic, first extracts the destination information, and then automatically passes over the remainder of the code to arrive at the next code of the text string. By so indicating the tab destination in the tab code, a tab operation is enabled to be independent of the active tab settings at the time of playback. Accordingly, the operator need not be concerned with resetting the tabs to their original condition when at a later time a document is printed from storage. And, by providing travel distance information, it is possible to back over or erase a tab operation without loss of correspondence between the print position and the reference point in the stored text string.