In an image forming apparatus, a controller performs processes in accordance with an operation mode settable to one of a first subscription mode and a second subscription mode. The first subscription mode corresponds to a first subscription in which a specific-color cartridge is a subscription subject and a non-specific-color cartridge is not the subscription subject. The second subscription mode corresponds to a second subscription in which both the specific-color cartridge and the non-specific-color cartridge are the subscription subject. The controller performs restricting usage of the non-specific-color cartridge in a case where the first subscription mode is set as the operation mode and the type information of the non-specific-color cartridge indicates the subscription type, compared to a case where the second subscription mode is set as the operation mode and the type information of the non-specific-color cartridge indicates the subscription type.

An image forming apparatus includes: a drum cartridge to which one of a first toner cartridge and a second toner cartridge is attachable; a frame including a first slot and a second slot; and a controller including a control memory and a processor. The drum cartridge to which the one of the first toner cartridge and the second toner cartridges is attached is attachable to one of the first slot and the second slot. The control memory stores first color information allocated to the first slot, and second color information allocated to the second slot. In a state where the drum cartridge is attached to one of the first slot and the second slot and when the drum memory does not store any color information, the processor is configured to perform: writing, into the drum memory, one of the first color information and the second color information which is appropriate.

A developing cartridge includes a developing roller, a shaft, a gear, an electric contact, and a gear cover. The developing roller is rotatable about a first axis extending in a predetermined direction and includes a developing roller shaft extending along the first axis. The shaft extends in the predetermined direction and has a peripheral surface. The gear is rotatable about the shaft. The electric contact is positioned at the peripheral surface of the shaft. The gear cover covers at least a portion of the gear and electrically connects the electric contact and the developing roller shaft.

A cartridge includes a detection gear and a memory. The detection gear may be rotatable about a first axis extending in a predetermined direction. The detection gear may include a first protrusion movable with rotation of the detection gear. The memory may include a first storage region configured to store, based on the motion of the first protrusion, new product determination information representing that the cartridge is detected as a new product.

In an authenticity determination system, an image forming apparatus acquires apparatus identification information for identifying the image forming apparatus from a memory of the image forming apparatus, and consumables container identification information for identifying a container of predetermined consumables from the container of the consumables mounted in the image forming apparatus. A server stores the apparatus identification information and the consumables container identification information in association with each other, receives the apparatus identification information and the consumables container identification information transmitted from the image forming apparatus, and determines whether the received apparatus identification information and the received consumables container identification information are stored in association with each other. When the information on the determination is affirmative, the image forming apparatus executes printing based on output source identification information including the apparatus identification information and the consumables container identification information on an output using the predetermined consumables.

In an example, a method comprises fabricating a first validation device for association with a first replaceable print apparatus component. The device may be to form part of circuitry arranged on the first replaceable print apparatus component, and may provide an associated electrically detectable characteristic which varies with the position of at least part of the first validation device. The electrically detectable characteristic may be measured and data indicative of the characteristic may be stored in a first memory. The first replaceable print apparatus component comprising the first device and the first memory may be assembled.

An example operation method of an image forming apparatus includes obtaining, through a sensor in the image forming apparatus, toner data corresponding to an amount of toner remaining in a developing apparatus, obtaining, based on the toner data in every predetermined period, a linear prediction model predicting the amount of toner remaining in the developing apparatus according to a time at which the toner is supplied to the developing apparatus, predicting, based on the linear prediction model, an expected supply time required for the amount of toner remaining in the developing apparatus to reach a target level, and controlling an operation of supplying the toner to the developing apparatus according to a result of comparing the expected supply time with a predetermined reference supply time.

An image forming apparatus includes 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 includes a drum memory that stores drum identification information. The toner cartridge includes 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.

In an image forming apparatus a toner cartridge includes a toner memory storing toner identification information. The toner cartridge is detachably attachable to a drum cartridge. The drum cartridge includes a drum memory storing drum identification information. The drum cartridge is detachably attached to the main-body casing. A controller performs a request process to request execution of a density correction process to correct a density of developer, in a case where a toner identification information determination process determines that the toner identification information stored in the toner memory does not match the toner identification information which is stored in the main-body memory in a toner identification information storing process or a drum identification information determination process determines that the drum identification information stored in the drum memory does not match the drum identification information which is stored in the main-body memory in the drum identification information storing process.

In some examples, an apparatus can include a mating interface coupled to a dispense interface to interact with a print particle dispense nozzle, a locking mechanism coupled to the dispense interface to prevent the print particle dispense nozzle from depositing a print particle to the dispense interface, and an authentication mechanism coupled to the locking mechanism to: authenticate the print particle dispense nozzle, and unlock the locking mechanism when the print particle dispense nozzle is authenticated to allow the print particle dispense nozzle to deposit the print particle to the dispense interface.