Printer controller for supplying data to a printhead module having one or more redundant nozzle rows

A printer controller for supplying dot data to a printhead module comprising at least first and second rows configured to print ink of a similar type or color, at least some nozzles in the first row being aligned with respective corresponding nozzles in the second row in a direction of intended media travel relative to the printhead, the printhead module being configurable such that the nozzles in the first and second rows are fired such that some dots output to print media are printed to by nozzles from the first row and at least some other dots output to print media are printed to by nozzles from the second row, the printer controller being configurable to supply dot data to the printhead module for printing, the printer controller being installed in a printer comprising:

• a printhead comprising first and second elongate printhead modules, the printhead modules being parallel to each other and being disposed end to end on either side of a join region, wherein the first printhead module is longer than the second printhead module;
• at least first and second printer controllers configured to receive print data and process the print data to output dot data to the printhead, wherein;
• the first printer controller outputs dot data to both the first printhead module and the second printhead module;
• and the second printer controller outputs dot data to the second printhead module.