A printer for printing an interface onto a surface is provided. The interface is comprised of visible data and machine-readable coded data. The visible data is based at least partially on document data which includes identity data indicative of an identity associated with a region of the interface. The printer comprises a printhead and a processor for generating dot data for the printhead using the document data. The processor includes a coded data generator configured to generate the coded data based at least partially on the identity data. Further, the printhead is configured to print the interface onto the surface by printing the visible data and the coded data substantially simultaneously.