An image forming apparatus comprises a main unit, a main unit memory, a drum cartridge, a toner cartridge, and a controller. The main unit memory stores printer identification information. The drum cartridge comprises a drum memory that stores drum identification information. The toner cartridge comprises a toner memory that stores toner identification information. The controller is configured to store in the main unit memory the drum identification information stored in the drum memory and store in the drum memory the printer identification information stored in the main unit memory, if it determines that the drum cartridge installed in the main unit is new, and store in the main unit memory the toner identification information stored in the toner memory and store in the toner memory the drum identification information stored in the drum memory, if it determines that the toner cartridge installed in the main unit is new.

A memory control device includes a memory control part that controls memory through an interface part in accordance with a predetermined communication regulation, an illegal access detection part that detects an illegal access to the memory according to an access state from the memory control part to the memory and a signal state of the interface part, and a signal control part that switches the signal state of the interface part from a write-allowed state, in which the interface part is able to be written, to a write-inhibited state, in which the interface part is protected from being rewritten, when the illegal access is detected by the illegal access detection part.

An image forming apparatus includes: an image bearing member; a developing device that develops an electrostatic latent image formed on the image bearing member; an attachment portion to which a developer supply container containing developer is attached; an information reading portion that reads information on the developer supply container stored in an information storage portion disposed in the developer supply container; a conveyance portion that communicates with a discharge port for discharging developer of the developer supply container and the developing device and conveys developer discharged from the developer supply container attached to the attachment portion to the developing device; a discharge mechanism that discharges developer from the developer supply container; and a controller that controls an operation of the discharge mechanism to reach a set discharged developer quantity using the information read by the information reading portion.

An example operation method of an image forming apparatus includes determining a state of a toner refill operation of injecting toner from a toner reload kit (TRK) into a cartridge in the image forming apparatus, based on completion of injecting toner from the TRK into the cartridge, controlling the TRK to store information indicating a toner refill completion in a memory of the TRK and updating information of an amount of remaining toner of the cartridge based on an amount of the toner injected into the cartridge from the TRK.

A toner container includes a container body, an opening, a cover, a toner discharge port, a shutter, a cylindrical structure, protrusions, and an identifier. The shutter is attached to the cover and includes a main shutter covering the toner discharge port. The main shutter moves between a closed position to close the toner discharge port and an open position to open the toner discharge port. The protrusions are on both sides of the cover and protrude in a direction orthogonal to a toner container mounting direction. The identifier is on the cover to indicate a toner color. The cylindrical structure's leading end is downstream of leading ends of the protrusions in the mounting direction. The main shutter's leading end is downstream of the protrusions' leading ends in the mounting direction when the main shutter is in the closed position. The protrusions are downstream of the identifier in the mounting direction.

An electronic component includes a processor and a memory. The electronic component has a secure platform capable of storing at least one dual key pair and a corresponding digital signature. There is also a system including a host machine and an electronic component capable of being operated by the host machine. The electronic component has a processor, a memory, and a secure platform capable of storing at least one dual key pair and a corresponding digital signature. Another aspect describes a method, which includes reading a public key from an electronic component by a host machine, verifying the public key against a stored key in the host machine, digitally signing data using a private key from the electronic component, verifying the signed data against the stored key, and using the electronic component by the host machine only if the signed data and the public key are verified.

An operation method of an image forming apparatus including determining a state of a toner refill operation of injecting toner from a toner reload kit (TRK) to a cartridge in the image forming apparatus; when determined the injecting of the toner into the cartridge is completed, controlling the TRK to store information indicating a toner refill completion in a memory of the TRK; and updating information of an amount of remaining toner of the cartridge, based on an amount of the toner injected into the cartridge from the TRK.

A replaceable item for a host device, such as a print substance cartridge for a printing device, stores multiple identities. For each identity, the replaceable item stores multiple authentication values, or passwords. The replaceable item selects an identity, and in response to a request for an authentication value from the host device, sends the requested authentication value for the selected identity.

A developing device to prevent damage of a memory unit and poor connection between terminals of the memory unit and a main body of an image forming apparatus, by improving a mounting position of the memory unit. The developing device is removably mounted to a main body of the image forming apparatus. The memory unit includes terminals exposed through a rear side of the developing device. The memory unit is disposed closer to a power reception unit formed at one side of the developing device than to a driving force reception unit formed at an other side of the developing device.

A toner container includes a container body, an opening, a cover, a toner discharge port, a shutter, a cylindrical structure, protrusions, and an identifier. The shutter is attached to the cover and includes a main shutter covering the toner discharge port. The main shutter moves between a closed position to close the toner discharge port and an open position to open the toner discharge port. The protrusions are on both sides of the cover and protrude in a direction orthogonal to a toner container mounting direction. The identifier is on the cover to indicate a toner color. The cylindrical structure's leading end is downstream of leading ends of the protrusions in the mounting direction. The main shutter's leading end is downstream of the protrusions' leading ends in the mounting direction when the main shutter is in the closed position. The protrusions are downstream of the identifier in the mounting direction.