Lexmark International, Inc.

Nathan Wayne Foley

Jennifer Topmiller Williams

Gregory Scott Woods

Timothy John Rademacher

Jimmy Daniel Moore, Jr

Christopher Alan Adkins

Zachary Nathan Fister

Patrick Laurence Kroger

Stephen Porter Bush

Martin Alan Johnson

Tommy Otis Lowe

Michael Duane Donovan

Timothy Lee Anderson

James Alan Ward

James Lesesne Bush, Iii

James Patrick Sharpe

Keith Allen Wahnsiedler

Jimmy Daniel Moore

Jr Jimmy Daniel Moore

A method for determining the authenticity of a component in an electronic device, the method comprising: receiving a seed by a component in the electronic device; storing the seed in a block of non-volatile memory in the component; calculating, by the component, the output of a cryptographic function with the input based on the seed and storing the output in the block of non-volatile memory; iteratively calculating, by the component, the outputs of the cryptographic function wherein for each iteration the input for the cryptographic function is based on the seed and all previous outputs, and for each iteration storing the output in the block of non-volatile memory; and determining the authenticity of the component based on a selected output of the cryptographic function F, the selected output being one of the outputs stored in the block of non-volatile memory.

Methods and systems for determining the authenticity of a component

A method for determining the authenticity of an item, the method comprising: receiving, by an item, a seed; storing the seed in a block of non-volatile memory in the supply item follower component; calculating, by the item follower component, an output of a cryptographic function with the input based on the seed and storing the output in the block of non-volatile memory; iteratively calculating, by the item, the outputs of the cryptographic function wherein for each iteration the input for the cryptographic function is based on the seed and all previous outputs, and for each iteration storing the output in the block of non-volatile memory; and determining the authenticity of the item based on a selected output of the cryptographic function of the item, the selected output being one of the outputs stored in the block of non-volatile memory.

A toner container installable in an image forming device having a controller according to one example embodiment includes a housing having a reservoir for storing toner. A chip is positioned on the housing and configured to, after sending a first busy response to the controller of the image forming device, receive a second write command from the controller of the image forming device that is abbreviated relative to a first write command received from the controller of the image forming device and that requests the chip to send a response to the first write command. The chip is further configured to send a response to the first write command to the controller of the image forming device if upon receiving a read command corresponding to the second write command the chip has completed processing the first write command.

Communication between an image forming device and a replaceable supply item

A toner container installable in an image forming device having a controller according to one example embodiment includes a housing having a reservoir for storing toner. A chip is positioned on the housing and configured to receive a first write command from the controller of the image forming device. The chip is further configured to determine whether a transmission cycle bit of the first write command matches a transmission cycle bit of a second write command received by the chip from the controller of the image forming device previous to the first write command. The chip is further configured to resend to the controller of the image forming device a response to the second write command if the transmission cycle bit of the first write command matches the transmission cycle bit of the second write command.

A supply item has toner for use in an imaging device. A chip has memory storing quanta indicating allowed usage of the supply item over its lifetime and a multiplier correlating the quanta to toner mass. The imaging device requires quanta to conduct imaging operations and loads the quanta and multiplier by way of a certificate stored in the memory. The imaging device retrieves quanta from the chip over time and both devices keep tally. Initialization between the supply item and imaging device includes providing encrypted and unencrypted instances of firmware versions and certificates from the supply item that the imaging device can compare for security. Alternatively, the supply item defines a fuser assembly, imaging unit, intermediate transfer member, or other component installed for use in the imaging device.

Chip and supply item for imaging device, including communication

Disclosed is a method for tuning control signals associated with one or more memory devices. The method includes performing a number of memory access operations on at least one memory device and recording results of the memory access operations. Specifically, the memory access operations are performed with different time delays for a first edge of a control signal. The control signal used for capturing data is provided by the at least one memory device. The method further includes selecting a time delay from the time delays used in the memory access operations. Moreover, the method includes utilizing the selected time delay in performing subsequent memory access operations on the at least one memory device. Also disclosed is a system including at least one memory device and an integrated circuit operatively coupled to the at least one memory device. The system incorporates the method for tuning control signals.

Method for tuning control signal associated with at least one memory device

A method for calibrating a printhead includes printing a test pattern, scanning the test pattern to obtain calibration data, performing an ink drop velocity optimization for the printhead using the calibration data, and determining a bi-directional offset based on the calibration data.

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Lexington, KY, United States of America

Nathan Wayne Foley