Abstract: A printing apparatus is disclosed. The printing apparatus comprises a rotating housing comprising a wall with an inner side defining a chamber and an outer side. The wall has a bore communicating the inner side and the outer side, and the chamber is to receive a fluid container. The printing apparatus also comprises a fix frame holding the rotating housing. The printing apparatus further comprises an optical sensor comprising an emitter to issue a detecting optical signal through the bore and a receiver to receive a detected optical signal associated to the detecting optical signal. The detected signal is sent to a controller to determine whether the fluid container is present in the rotating housing.

Abstract: There is disclosed a method of supplying an n-channel transistor, operating as a voltage regulator, with a supply voltage and providing a control voltage to the n-channel transistor. The n-channel transistor is controlled by the control voltage to output an operating voltage of a printhead at a predetermined voltage.

Abstract: A system comprises a printhead including a nozzle, a temperature sensor and a processor. The temperature sensor detects the temperature of a location of a print surface upon firing the nozzle to eject a drop of printing fluid to the location of the print surface. The processor determines whether the nozzle ejected the drop properly using the detected temperature.

Abstract: There is provided a print apparatus and a media roll for the print apparatus, comprising a media identifier located on an end of a core section of the media roll. A type of media loaded into the print apparatus is determined by sensing the media identifier on the media roll using a non-contact sensor to scan the end of the core section.

Abstract: A printing apparatus is disclosed. The printing apparatus comprises a rotating housing comprising a wall with an inner side defining a chamber and an outer side. The wall has a bore communicating the inner side and the outer side, and the chamber is to receive a fluid container. The printing apparatus also comprises a fix frame holding the rotating housing. The printing apparatus further comprises an optical sensor comprising an emitter to issue a detecting optical signal through the bore and a receiver to receive a detected optical signal associated to the detecting optical signal. The detected signal is sent to a controller to determine whether the fluid container is present in the rotating housing.

Abstract: Disclosed herein is an electric motor control circuit, a printing device, and a method of overvoltage protection for an electric motor. The electric motor control circuit comprises a controller, a voltage converter to generate a supply voltage of the controller from a voltage at terminals of the electric motor and a switchable braking circuit connected to the motor terminals. The controller is to activate the braking circuit if the voltage at the motor terminals exceeds a threshold voltage while the controller is in an off-state.

Abstract: There is disclosed a method of supplying an n-channel transistor, operating as a voltage regulator, with a supply voltage and providing a control voltage to the n-channel transistor. The n-channel transistor is controlled by the control voltage to output an operating voltage of a printhead at a predetermined voltage.

Abstract: A system comprises a printhead including a nozzle, a temperature sensor and a processor. The temperature sensor detects the temperature of a location of a print surface upon firing the nozzle to eject a drop of printing fluid to the location of the print surface. The processor determines whether the nozzle ejected the drop properly using the detected temperature.

Abstract: It is disclosed a motor identification method for determine possible incorrect connections in a system comprising a plurality of motors corresponding to a plurality of sub-systems, the method comprising: applying an input to at least one of the motors causing its movement; and determining a detection signal corresponding to a position, speed or acceleration of the motor during a detection period; wherein the system comprises a memory storing a set of characteristic signals corresponding to at least some of the sub-systems and wherein the method comprises comparing, by a controller, the detection signal with the set of characteristic signals and correlating the at least one of the motors to a determined sub-system.

Abstract: Example systems to determine print fluid ejection nozzle health for a printer device are disclosed along with corresponding methods. In an example, the system includes an image recording device to record an image of print fluid ejected from a print fluid ejection nozzle and disposed on a printable surface. In addition, the system includes an image processor to analyse the image to provide a result based on a characteristic of the image that are representative of the print fluid disposed on the printable surface. Further, the system includes a controller to receive the result and assign a nozzle health category to the print fluid ejection nozzle in dependence on the result.

Abstract: Devices and methods for calibrating communication lines are disclosed. A clock sets a frequency of transmission through a communication line. A delay compensator, comprising multi-tap delay lines introduces delays in a transmitted message to compensate for skew in the communication line. An error comparator, coupled to the delay compensator, identifies errors in the messages transmitted through the multi-tap delay lines above an error margin. A delay selector, coupled to the error comparator and to the delay compensator, selects taps of the multi-tap delay lines of the delay compensator. Taps of the multi-tap delay lines where no errors are identified for the selected clock frequency are stored in a memory.

Abstract: Devices and methods for calibrating communication lines are disclosed. A clock sets a frequency of transmission through a communication line. A delay compensator, comprising multi-tap delay lines introduces delays in a transmitted message to compensate for skew in the communication line. An error comparator, coupled to the delay compensator, identifies errors in the messages transmitted through the multi-tap delay lines above an error margin. A delay selector, coupled to the error comparator and to the delay compensator, selects taps of the multi-tap delay lines of the delay compensator. Taps of the multi-tap delay lines where no errors are identified for the selected clock frequency are stored in a memory.

Abstract: A diagnostic device comprises a comparison section to compare an input voltage with a threshold voltage, wherein the input voltage is a power supply voltage for a component on a circuit board; and an indicator to provide an indication of the result of the comparison by the comparison section, the indication to render the circuit board identifiable to direct inspection, wherein the supply of power to the component is independent of the result of the comparison.

Abstract: A printer is disclosed. The printer uses a target located on one side of media to position an image on the other side of the media. The printer backlights the media and uses a sensor that locates the target through the backlit media.

Abstract: A printer is disclosed. The printer uses a target located on one side of media to position an image on the other side of the media. The printer backlights the media and uses a sensor that locates the target through the backlit media.

Abstract: A printer is disclosed. The printer uses a target located on one side of media to position an image on the other side of the media. The printer backlights the media and uses a sensor that locates the target through the backlit media.

Abstract: A printer is disclosed. The printer uses a target located on one side of media to position an image on the other side of the media. The printer backlights the media and uses a sensor that locates the target through the backlit media.

Abstract: According to one example, there is provided a system for compensating for changes in printhead-to-printhead spacing in a printing system having multiple printheads mountable on a printhead support. The system includes a measurement system to determine a change in printhead-to-printhead spacing between different ones of mounted printheads, and a processor to determine compensation to be applied to the printing system to compensate for the determined change in printhead-to-printhead spacing.

Abstract: According to one example, there is provided a system for compensating for changes in printhead-to-printhead spacing in a printing system having multiple printheads mountable on a printhead support. The system comprises a measurement system to determine a change in printhead-to-printhead spacing between different ones of mounted printheads, and a processor to determine compensation to be applied to the printing system to compensate for the determined change in printhead-to-printhead spacing.

Abstract: A power supply circuit has parallel supply and control branches each with fuses, the power supply branch comprising at least one replaceable fuse. The supply branch is connected to one or more electrical components of an electrical device, such as the actuator and sensors of a printer, and the supply branch is connected to control or monitoring components. A circuit comprising lights indicates correct or faulty operation of the various parts of the supply circuit.