Abstract: According to one embodiment, an interface system includes a receiver, a first clock generator, a second clock generator, and a sampling circuit. The receiver is configured to receive a first clock and serial data from a host. The first clock generator includes a first voltage controlled oscillator (VCO) and is configured to generate a second clock on the basis of the first clock. The second clock generator includes a second voltage controlled oscillator (VCO) and is configured to generate a third clock on the basis of the serial data. The sampling circuit is configured to sample reception data on the basis of the third clock and the serial data.

Abstract: According to one embodiment, a memory device includes a nonvolatile semiconductor memory having physical storage areas that includes a user area externally accessible and are divided into management units and a control unit. The control unit receives a control command having a first argument to designate a sequential write area and a read command or a write command, assigns a management unit represented by an address of the read command or the write command as the sequential write area, and changes memory access control by judging whether an address of a memory access command to access the user area indicates access in the sequential write area whose size is equivalent to the management unit.

Abstract: According to one embodiment, a memory device includes a nonvolatile semiconductor memory having physical storage areas that includes a user area externally accessible and are divided into management units and a control unit. The control unit receives a control command having a first argument to designate a sequential write area and a read command or a write command, assigns a management unit represented by an address of the read command or the write command as the sequential write area, and changes memory access control by judging whether an address of a memory access command to access the user area indicates access in the sequential write area whose size is equivalent to the management unit.

Abstract: According to one embodiment, a memory device includes a nonvolatile semiconductor memory having physical storage areas that includes a user area externally accessible and are divided into management units and a control unit. The control unit receives a control command having a first argument to designate a sequential write area and a read command or a write command, assigns a management unit represented by an address of the read command or the write command as the sequential write area, and changes memory access control by judging whether an address of a memory access command to access the user area indicates access in the sequential write area whose size is equivalent to the management unit.

Abstract: When initializing a card-shaped device inserted in a card interface, operation mode acquiring means incorporated in an electronic device acquires operation mode information, stored in a register file incorporated in the card-shaped device, by a predetermined procedure using a predetermined pin. Operation mode setting means incorporated in the electronic device executes signal assignment on a plurality of data pins peculiar to an operation mode indicated by the acquired operation mode information, thereby switching a data transfer width, and allowing the card-shaped device to operate in the operation mode.

Abstract: A host apparatus, into which a card having a nonvolatile semiconductor memory is inserted, issues a check command to the card. The check command instructs to send information on whether the card supports a termination process in which the card shifts into a state ready for a stop of power supply from the host apparatus.

Abstract: A host apparatus, into which a card having a nonvolatile semiconductor memory is inserted, issues a check command to the card. The check command instructs to send information on whether the card supports a termination process in which the card shifts into a state ready for a stop of power supply from the host apparatus.

Abstract: According to one embodiment, there is provided a memory system including a power supply terminal, a plurality of couplers, and a control unit. The power supply terminal is a terminal to be connected to a power supply line of a host. The plurality of couplers are couplers to be electromagnetically coupled respectively to couplers of the host. The control unit can establish a reception channel and a transmission channel that are independent of each other between the memory system and the host via the plurality of couplers according to level of a power supply voltage supplied from the host via the power supply line and the power supply terminal.

Abstract: An expansion device includes a clock swing detecting unit, a command receiving unit, and a response generating unit. The clock swing detecting unit detects a clock swing set based on a second signal voltage lower than a first signal voltage before the start of initialization. The command receiving unit receives a command having a parameter incorporated that can indicate which signal voltage of the first signal voltage and second signal voltage is being used. The response generating unit responds to the command based on the clock swing.

Abstract: According to one embodiment, a host controller includes a command generator and detector. The command generator generates a command having a retransmission flag in an argument, and transmits the generated command to a memory device. The detector detects timeout if a response from the memory device cannot be recognized within a defined time. When transmitting an initial command, the host controller clears the retransmission flag and transmits the command. If the detector detects timeout, the host controller sets the retransmission flag, and retransmits the same command as the initial command to the device. If a normal response corresponding to the initial command or retransmitted command is received, the host controller recognizes that the command is correctly executed.

Abstract: When initializing a card-shaped device inserted in a card interface, operation mode acquiring means incorporated in an electronic device acquires operation mode information, stored in a register file incorporated in the card-shaped device, by a predetermined procedure using a predetermined pin. Operation mode setting means incorporated in the electronic device executes signal assignment on a plurality of data pins peculiar to an operation mode indicated by the acquired operation mode information, thereby switching a data transfer width, and allowing the card-shaped device to operate in the operation mode.

Abstract: A host device is configured to read and write information from and into a card and to supply a supply voltage that belongs to a first voltage range or a second voltage range which is lower than the first voltage range, and issues a voltage identification command to the card. The voltage identification command includes a voltage range identification section, an error detection section, and a check pattern section. The voltage range identification section includes information indicating which one of the first voltage range and the second voltage range the supply voltage belongs. The error detection section has a pattern configured to enable the card which has received the voltage identification command to detect errors in the voltage identification command. The check pattern section has a preset pattern.

Abstract: A memory card 100 having a NAND type flash memory connectable to a host device 200, capable of transmitting/receiving a signal to/from the host device 200 at a first voltage (3.3 V) or a second voltage (1.8 V) and safely changing a signal voltage of a transmission/reception signal that mutually checks a signal voltage through handshake processing with the host device 200 when the signal voltage is switched.

Abstract: When initializing a card-shaped device inserted in a card interface, operation mode acquiring means incorporated in an electronic device acquires operation mode information, stored in a register file incorporated in the card-shaped device, by a predetermined procedure using a predetermined pin. Operation mode setting means incorporated in the electronic device executes signal assignment on a plurality of data pins peculiar to an operation mode indicated by the acquired operation mode information, thereby switching a data transfer width, and allowing the card-shaped device to operate in the operation mode.

Abstract: According to one embodiment, a memory system, such as a SDIO card, includes a nonvolatile semiconductor memory device, a control section, a memory, an extended function section, and an extension register. The extended function section is controlled by the control section. A first command reads data from the extension register in units of given data lengths. A second command writes data to the extension register in units of given data lengths. A extension register includes a first area, and second area different from the first area, information configured to specify a type of the extended function and controllable driver, and address information indicating a place to which the extended function is assigned, the place being on the extension register, are recorded in the first area, and the second area includes the extended function.

Abstract: According to one embodiment, a device includes a semiconductor memory and a controller. The semiconductor memory includes first and second areas which are accessible from an outside. The controller controls the semiconductor memory. The device includes an unlocked state where accessing the first area is allowed, and a locked state where the accessing the first area is prohibited. The device is capable of holding one or more user key in the device. The device includes a function of configuration operation to register, change, and delete the user key in the semiconductor memory.

Abstract: According to one embodiment, a semiconductor device includes a device. The device includes a decoder, a generation circuit, a register, and a modifier. The decoder analyzes a command of a received packet. The generation circuit generates a unique device number in accordance with information in the packet. The register holds the generated unique device number. The modifier updates and outputs the packet. When a packet issued by a host is a command packet, among broadcast packets which return to the host through one or more devices, for determining the unique device number, the command packet includes parameters of an initial value and final value of device number.

Abstract: A memory card 100 having a NAND type flash memory connectable to a host device 200, capable of transmitting/receiving a signal to/from the host device 200 at a first voltage (3.3 V) or a second voltage (1.8 V) and safely changing a signal voltage of a transmission/reception signal that mutually checks a signal voltage through handshake processing with the host device 200 when the signal voltage is switched.

Abstract: According to one embodiment, a memory system, such as a SDIO card, includes a nonvolatile semiconductor memory device, a control section, a memory, an extended function section, and an extension register. The extended function section is controlled by the control section. A first command reads data from the extension register in units of given data lengths. A second command writes data to the extension register in units of given data lengths. A extension register includes a first area, and second area different from the first area, information configured to specify a type of the extended function and controllable driver, and address information indicating a place to which the extended function is assigned, the place being on the extension register, are recorded in the first area, and the second area includes the extended function.

Abstract: A host device is configured to read and write information from and into a card and to supply a supply voltage that belongs to a first voltage range or a second voltage range which is lower than the first voltage range, and issues a voltage identification command to the card. The voltage identification command includes a voltage range identification section, an error detection section, and a check pattern section. The voltage range identification section includes information indicating which one of the first voltage range and the second voltage range the supply voltage belongs. The error detection section has a pattern configured to enable the card which has received the voltage identification command to detect errors in the voltage identification command. The check pattern section has a preset pattern.