A noncontact communication medium includes a power generator that has a coil and generates power with application of an external magnetic field from an outside to the coil, a clock signal generator that generates a clock signal using the power, and a processor that operates using the power and executes processing on a command included in the external magnetic field. In a case where a processing result signal indicating a processing result obtained with the execution of the processing is transmitted to the outside through the external magnetic field by the coil, the processor changes a signal level of the processing result signal according to intensity of the external magnetic field.

Provided is a recording tape cartridge including: a case that is configured by causing a peripheral wall of an upper case and a peripheral wall of a lower case to abut against each other and accommodates a reel on which a recording tape is wound; a reference surface that is formed on the lower case and serves as a reference in an axial direction of the reel in a case where the case is loaded into a drive device; a noncontact communication medium on which individual information is recorded, the noncontact communication medium being accommodated in the lower case and having a plate shape; a supporting portion that is formed on the lower case and supports the noncontact communication medium such that the noncontact communication medium is disposed while being inclined with respect to the reference surface at an angle of approximately 45 degrees; a position restricting portion that is formed on the lower case and restricts a position of a lower end portion of the noncontact communication medium; and a retaining portion that is formed on the lower case and retains an upper end portion of the noncontact communication medium.

The magnetic tape includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder. A dimension change amount Δw in a width direction with respect to a tension change in a longitudinal direction is 400 ppm/N to 900 ppm/N, the magnetic layer includes a plurality of servo bands, and a coefficient of variation CV calculated by Equation A: CV=(σG/Δw)×100 is 10% or less. The σG is a standard deviation of servo band intervals measured in a region of the magnetic tape over 100 m in the longitudinal direction with a tension of 0.6 N in the longitudinal direction. A magnetic tape container containing the magnetic tape.

A cartridge memory used for a tape cartridge includes: a communication unit that communicates with a recording and reproducing device using a wireless communication method defined by an ISO 14443-2 standard which is a wireless communication standard; a non-volatile memory with a storage capacity exceeding 16 KB; and a control unit that writes or reads data to or from the non-volatile memory on a word-by-word basis (2 bytes at a time) or on a block-by-block basis (32 bytes at a time). The non-volatile memory includes a plurality of memory banks each having a storage capacity of 128 KB or less. The control unit writes or reads data defined by a magnetic tape standard to or from one or two or more first memory banks among the plurality of the memory banks, and writes or reads additional data to or from one or two or more second memory banks other than the first memory bank.

A magnetic tape cartridge including: a magnetic tape; and a recording medium including a predetermined area for recording defect information, which is information regarding a defect of the magnetic tape detected in a production process of the magnetic tape. A recording device, a recording method, a data recording and reproducing system, and a data recording and reproducing method are also provided.

A noncontact communication medium includes a processor, and a memory incorporated in or connected to the processor, and performs noncontact communication with an external communication device. The memory has a storage block where information regarding an attribute of the noncontact communication medium is stored and that includes a plurality of storage fields. The plurality of storage fields include a specification-independent storage field where information independent of a specification of a magnetic tape cartridge, in which the noncontact communication medium is mounted, is stored. The processor is configured to write accompanying information regarding the magnetic tape cartridge in the specification-independent storage field in response to an instruction given from the external communication device to the noncontact communication medium by the noncontact communication.

A magnetic tape cartridge includes a case in which a magnetic tape is housed, and an NVM of a cartridge memory provided in the case. The NVM stores cartridge information including an identification ID regarding an allowable range of temperature/humidity in using the magnetic tape, an upper limit of a preservation period of the magnetic tape, and an upper limit of a use frequency of the magnetic tape.

A magnetic tape cartridge includes a case on which an identifier is displayed, and a storage medium in which reading condition information that is information regarding a condition for reading the identifier is stored.

A noncontact communication medium includes a processing circuit mounted on a substrate having a coil to induce power by action of an external magnetic field applied from an outside, and processing circuit having an internal capacitor; and an external capacitor externally attached to the processing circuit. The external capacitor, the internal capacitor, and the coil constitute a resonance circuit resonating at a predetermined resonance frequency by the action of the external magnetic field. The external capacitor is connected in parallel with the internal capacitor, and the resonance circuit has a Q-value determined in accordance with a characteristic of the external capacitor.

A magnetic tape cartridge includes a case in which a magnetic tape is housed, and an NVM of a cartridge memory provided in the case. The NVM stores cartridge information including an identification ID regarding an allowable range of temperature/humidity in using the magnetic tape, an upper limit of a preservation period of the magnetic tape, and an upper limit of a use frequency of the magnetic tape.