Toner Level Sensing for Replaceable Unit of an Image Forming Device

An electronic module for use with a replaceable unit of an image forming device for estimating an amount of toner remaining in a reservoir of the replaceable unit, the electronic module comprising:

• processing circuitry programmed:
• to receive pulses from a magnetic sensor, each pulse indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir;
• to count the number of the pulses received from the magnetic sensor;
• and
• upon receiving a request from a controller of the image forming device for the count of the pulses received from the magnetic sensor, to send the count of the pulses received from the magnetic sensor to the controller of the image forming device and to reset the count of the pulses received from the magnetic sensor.

A method for programming memory of a replaceable unit of an electrophotographic image forming device, the method comprising:

• determining an amount of toner in a reservoir of the replaceable unit;
• converting the amount of toner determined to an estimate of an amount of rotation of a shaft that will be sensed before the reservoir of the replaceable unit runs out of usable toner;
• and
• storing the estimate of the amount of rotation of the shaft that will be sensed before the reservoir of the replaceable unit runs out of usable toner in the memory of the replaceable unit.

An electronic module for use with a replaceable unit of an image forming device for estimating an amount of toner remaining in a reservoir of the replaceable unit, the electronic module comprising:

• processing circuitry and associated memory, the processing circuitry programmed:
• to receive pulses from a magnetic sensor, each pulse indicative that the magnetic sensor detected a magnet on a moving paddle positioned in the reservoir;
• to store in the memory associated with the processing circuitry a time stamp of each pulse received from the magnetic sensor;
• and
• upon receiving a request from a controller of the image forming device, to send to the controller of the image forming device a most recent time stamp stored in the memory associated with the processing circuitry.