A commodity-data processing apparatus comprising: a housing having a printer housing space; a printer unit mounted in the housing and movable between a housed position at which the printer unit fits in the printer housing space and a drawn-out position at which the printer unit is drawn out of the printer housing space, the printer unit including a cover that is movable between a closed position and an open position when the printer unit is at the drawn-out position and not movable between the closed position and the open position when the printer unit is at the housed position; a printing head attached to an inner side of the cover, the cover being positioned at a top portion of the printer unit, the printing head being movable as the cover moves, the printing head being capable of being drawn out from the housing section together with the printer unit; a scanner unit mounted in the housing, the scanner unit and the printer unit being vertically provided side by side, the printer unit being disposed under the scanner unit; a cover sensor configured to detect a position of the cover of the printer unit; and a controller configured to: determine whether the cover is moved from the open position to the closed position based on the detected position of the cover sensor, determine whether or not the printer unit is ready for printing, upon determining that the cover is moved from the open position to the closed position, and while the printer unit is in the drawn-out position, enable receipt printing by the printing unit, upon determining that the printer unit is ready for printing. a housing having a printer housing space; a printer unit mounted in the housing and movable between a housed position at which the printer unit fits in the printer housing space and a drawn-out position at which the printer unit is drawn out of the printer housing space, the printer unit including a cover that is movable between a closed position and an open position when the printer unit is at the drawn-out position and not movable between the closed position and the open position when the printer unit is at the housed position; a printing head attached to an inner side of the cover, the cover being positioned at a top portion of the printer unit, the printing head being movable as the cover moves, the printing head being capable of being drawn out from the housing section together with the printer unit; a scanner unit mounted in the housing, the scanner unit and the printer unit being vertically provided side by side, the printer unit being disposed under the scanner unit; a cover sensor configured to detect a position of the cover of the printer unit; and a controller configured to: determine whether the cover is moved from the open position to the closed position based on the detected position of the cover sensor, determine whether or not the printer unit is ready for printing, upon determining that the cover is moved from the open position to the closed position, and while the printer unit is in the drawn-out position, enable receipt printing by the printing unit, upon determining that the printer unit is ready for printing. determine whether the cover is moved from the open position to the closed position based on the detected position of the cover sensor, determine whether or not the printer unit is ready for printing, upon determining that the cover is moved from the open position to the closed position, and while the printer unit is in the drawn-out position, enable receipt printing by the printing unit, upon determining that the printer unit is ready for printing.