An image processing apparatus for a pagewidth inkjet printer that includes
an array of printhead chips that span a print area includes an elongate
support structure for supporting the array of printhead chips. A
plurality of printed circuit boards are mounted end-to-end on the support
structure. Each printed circuit board includes a memory device. An
application specific integrated circuit (ASIC) is connected to the memory
device. The ASIC is configured to accept data to be written to the memory
device and to write data from the memory device to a number of respective
printhead chips. A serial bus is connected to the ASIC to write data to
the ASIC. A microcontroller is connected to the ASIC so that the
microcontroller can write data to the memory device, via the ASIC. A
plurality of connectors is provided. Each connector is interposed between
a respective ASIC and respective printhead chips.