Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a magnetic sensor. Each pulse is indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir. The processing circuitry counts the number of the pulses received from the magnetic sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the magnetic sensor and resets the count of the pulses received from the magnetic sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a magnetic sensor. Each pulse is indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir. The processing circuitry counts the number of the pulses received from the magnetic sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the magnetic sensor and resets the count of the pulses received from the magnetic sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a sensor. The processing circuitry counts the number of the pulses received from the sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the sensor and resets the count of the pulses received from the sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a sensor. The processing circuitry counts the number of the pulses received from the sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the sensor and resets the count of the pulses received from the sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes rotating a shaft positioned in the reservoir and measuring an amount of revolution of the shaft. A paddle mounted on the shaft and free to fall ahead of the rotation of the shaft is pushed by the rotation of the shaft. An estimate of the amount of toner remaining in the reservoir is decreased based on the measured amount of revolution of the shaft. The paddle is sensed near a lowest center of gravity of the paddle. The estimate of the amount of toner remaining in the reservoir is adjusted when the number of times the paddle is sensed near the lowest center of gravity of the paddle per revolution of the shaft increases.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a magnetic sensor. Each pulse is indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir. The processing circuitry counts the number of the pulses received from the magnetic sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the magnetic sensor and resets the count of the pulses received from the magnetic sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes receiving by processing circuitry pulses from a magnetic sensor. Each pulse is indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir. The processing circuitry counts the number of the pulses received from the magnetic sensor. Upon receiving a request from a controller of the image forming device, the processing circuitry sends to the controller of the image forming device the count of the pulses received from the magnetic sensor and resets the count of the pulses received from the magnetic sensor.

Abstract: A method for estimating an amount of toner remaining in a reservoir of a replaceable unit for an image forming device according to one example embodiment includes rotating a shaft positioned in the reservoir and measuring an amount of revolution of the shaft. A paddle mounted on the shaft and free to fall ahead of the rotation of the shaft is pushed by the rotation of the shaft. An estimate of the amount of toner remaining in the reservoir is decreased based on the measured amount of revolution of the shaft. The paddle is sensed near a lowest center of gravity of the paddle. The estimate of the amount of toner remaining in the reservoir is adjusted when the number of times the paddle is sensed near the lowest center of gravity of the paddle per revolution of the shaft increases.

Abstract: An ink jet printhead voltage fault protection apparatus includes a power supply and a latching circuit. The latching circuit disables a printhead voltage applied to the printhead by the power supply upon detection of a fault condition associated with the printhead voltage such that the printhead voltage remains disabled until the power supply goes through a power-on reset sequence.

Abstract: An ink jet printhead voltage fault protection apparatus includes a power supply and a latching circuit. The latching circuit disables a printhead voltage applied to the printhead by the power supply upon detection of a fault condition associated with the printhead voltage such that the printhead voltage remains disabled until the power supply goes through a power-on reset sequence.

Abstract: A method of determining a feed position of a print medium in an imaging apparatus includes an encoder device, connected to a feed shaft, that produces a first periodic signal and a second periodic signal approximately 90 degrees out of phase with the first. A modified first signal is created. A modified second signal is created. The modified first signal is added to the modified second signal to create a summation signal that has a plurality of local minimum values, a plurality of local maximum values, and a plurality of substantially linear segments. A periodic modified summation signal is created by adding a corresponding constant value to each linear segment. The feed position of the print medium is calculated based upon a number of cycles of the modified summation signal counted and a determined value of the modified summation signals.

Abstract: An improved printer is provided which includes a print engine control program that minimizes the power consumption of the paper-handling devices to allow for a smaller DC power supply. Some of the paper-handling devices are input paper trays, output paper stackers, and a duplexer, which all preferably contain a microcontroller and an individual electric motor drive. The base printer also contains a microcontroller in the print engine that controls the printer's mechanisms and various subassemblies that are used in the laser electrophotographic printing process. To maintain control of the entire paper path, the print engine sends commands to the paper-handling devices, and these devices send responses to these commands. Most of the printer's paper-handling devices receive their electrical power entirely from the base printer, which is supplied as a DC voltage. The print engine avoids the concurrent running of subsystems in cases where the functionality of the printer is not compromised.

Abstract: Two stacked paper trays (43, 45) are connected electrically by cable (53) and are physically combined, as by bolts. The combined unit has a single microprocessor (49). The paper trays communicate status, such as paper size and paper amount to the microprocessor. The microprocessor reports upon interrogation from a control processor (61) of a printer (7) that it is a multiple tray unit and reports the status for each unit. This avoids the use of a microprocessor with each tray.