Abstract: The present technology relates to a communication device, a communication method, an integrated circuit, and an electronic instrument, which are capable of reducing a manufacturing cost of a communication device having both functions of an RF tag and reader/writer or an electronic instrument equipped with the communication device.

Abstract: A communication device includes: a communication unit configured to perform proximity communication with a reader/writer; and a control unit configured to control writing of data as to nonvolatile memory in accordance with a command from the reader/writer; with the control unit writing data in a buffer unit that serves as a buffer to buffer data to be written, in accordance with a command from the reader/writer, writing the unit number of an object unit that is a unit to be written with data as the unit number of the buffer unit, and taking the object unit as a new buffer unit, thereby performing writing of data in the object unit; and with the control unit being activated by an RF signal being received from the reader/writer, and erasing all of the pages of the buffer unit during activation processing to be performed before receiving a command from the reader/writer.

Abstract: The present technology relates to a communication device, a communication method, an integrated circuit, and an electronic instrument, which are capable of reducing a manufacturing cost of a communication device having both functions of an RF tag and reader/writer or an electronic instrument equipped with the communication device.

Abstract: Provided is a communication device including: a communication section performing proximity communication with a reader/writer; a storage section storing data and a sequence number; and a control section controlling the writing of the data to the storage section in accordance with a command from the reader/writer. The communication section sends the sequence number to the reader/writer and receives first encryption data, which is generated by the reader/writer using a value based on the sequence number and writing target data which is target data which is written into the storage section, and the writing target data from the reader/writer, and the control section generates second encryption data using the value based on the sequence number and the writing target data, writes the writing target data into the storage section, and updates the sequence number in a case where the first encryption data and the second encryption data match.

Abstract: Provided is a communication device including: a communication section performing proximity communication with a reader/writer; a storage section storing data and a sequence number; and a control section controlling the writing of the data to the storage section in accordance with a command from the reader/writer. The communication section sends the sequence number to the reader/writer and receives first encryption data, which is generated by the reader/writer using a value based on the sequence number and writing target data which is target data which is written into the storage section, and the writing target data from the reader/writer, and the control section generates second encryption data using the value based on the sequence number and the writing target data, writes the writing target data into the storage section, and updates the sequence number in a case where the first encryption data and the second encryption data match.

Abstract: A communication device includes: a communication unit configured to perform proximity communication with a reader/writer; and a control unit configured to control writing of data as to nonvolatile memory in accordance with a command from the reader/writer; with the control unit writing data in a buffer unit that serves as a buffer to buffer data to be written, in accordance with a command from the reader/writer, writing the unit number of an object unit that is a unit to be written with data as the unit number of the buffer unit, and taking the object unit as a new buffer unit, thereby performing writing of data in the object unit; and with the control unit being activated by an RF signal being received from the reader/writer, and erasing all of the pages of the buffer unit during activation processing to be performed before receiving a command from the reader/writer.

Abstract: A transmission circuit transmits a command to a contactless IC card. A receiving circuit receives a transmission signal from the IC card and an amplifying circuit in the receiving circuit amplifies the reception signal. An impedance element to which the reception signal is applied is provided at a preliminary stage of the amplifying circuit. The impedance element is controlled so that the impedance thereof is lowered, and an input signal to be input into the amplifying circuit is muted.

Abstract: A transmission circuit transmits a command to a contactless IC card. A receiving circuit receives a transmission signal from the IC card and an amplifying circuit in the receiving circuit amplifies the reception signal. An impedance element to which the reception signal is applied is provided at a preliminary stage of the amplifying circuit. The impedance element is controlled so that the impedance thereof is lowered, and an input signal to be input into the amplifying circuit is muted.