Form overlay type printing apparatus

Claim 1

A form overlay type document printing apparatus for receiving from a host computer form data, repetition data which remains constant for a first number of sequential pages of a document, and variable data which varies with each page of the document, and for producing a printed output corresponding thereto, the apparatus comprising: a format memory for storing form data; a repetition data memory for storing repetition data; a variable data buffer for storing variable data; input data means for supplying form data, repetition data, and variable data received from the host computer to said format memory, said repetition data memory, and said variable data buffer, respectively; a form pattern generator for generating form printing signals corresponding to said format data stored in said format memory; a printing pattern generator for generating repetition printing signals corresponding to said repetition data and variable printing signals corresponding to said variable data; a form pattern buffer for combining said form printing signals and said repetition printing signals to output a selected sequence of combined printing signals for a succession of documents; an output buffer for combining said combined printing signals with said variable printing signals to produce corresponding print driver signals for each document in said succession of documents; and means, responsive to said print driver signals, for printing said succession of documents, whereby only said variable data need be transferred from said host computer for each of said sequential documents pages.