HIGH SPEED PRINTER

An electronic printing system for printing digitally stored images is disclosed which achieves extremely high throughputs as a consequence of control of the addressing of various memory sections being allocated to hardware assist units which operate independently of the processing unit. The processing unit rotates words retrieved from a font storage memory with respect to word boundaries in a page memory of a raster storage unit at high speed to achieve proper positioning of the words for storage in the page memory. The system further has a readout system for reversing the order of readout of the significance of pixels of words stored in both the font storage memory and from the combined output of the raster storage unit and the raster form storage unit which cuts in half the necessary storage requirements of character orientations in the font storage unit for duplex printing and printing on either side of a page for pages which have been punched for storage in ring binders. Finally, an addressing unit is provided for the raster storage unit which generates all addresses for storage of words in the page memories independently of the operation of the processing unit with the exception of the first word of the first character which is generated by the processing unit.