29. An apparatus according to claim 19, wherein said document memory is formed in an integrated circuit card.
19. A handheld data input apparatus comprising: a pressure-sensitive tablet; a coordinate detector for receiving a signal output from said tablet and outputting coordinate data corresponding to a pressed position on a detection surface of said tablet; a character processing means for extracting predetermined character data from time-serial coordinate data output from said coordinate detector; a document memory for sequentially storing the character data extracted by said character processing means; selection means for selecting the character data stored in said document memory or coordinate data from said coordinate detector; an interface means for outputting the character data or the coordinate data selected by said selection means to a host apparatus connected to said handheld data input apparatus; and a casing integrally incorporating said tablet, said coordinate detector, said character processing means, said document memory, said selection means, and said interface means.