According to an embodiment, a printer includes a battery, a display, a memory and a processor. The memory stores a predetermined residual capacity of the battery of the printer and amount information of a printing medium on which a predetermined printing data can be printed with the predetermined residual capacity in association with each other in advance. The processor controls the display such that the amount information corresponding to the predetermined residual capacity stored in the memory is displayed on the display, in a case where determining that the residual capacity of the battery is reduced to less than the predetermined residual capacity.

Provided is an electric apparatus including a reception unit (for example, hardware key) for receiving an instruction relating to functions of the electric apparatus and having operation states of a power conserving state in which power required for performing the functions thereof is limited and a normal state in which the power is not limited, wherein the reception unit may receive an instruction indicating a return to the normal state in the power conserving state and receive an instruction which is to be originally received in the normal state. When the reception unit receives the instruction, signals at different levels are output depending on the operation state and based on the signal to be output, a return signal relating to the return to the normal state or an execution signal relating to the execution of a function corresponding to the instruction received by the receiving signal is output.

Provided is a printing apparatus configured to perform printing on a print medium by using a printing unit, the printing apparatus including: a power storage unit capable of storing power fed from an external power source connected via a USB cable; a measurement unit capable of measuring time based on power from the power storage unit; a control unit configured to execute predetermined processing based on a measurement result of the measurement unit; and a restriction unit capable of restricting power fed from the power storage unit. In a period in which power feed from the external power source is stopped, the restriction unit restricts feeding of power to units other than at least the measurement unit depending on a power storage amount of the power storage unit, and the measurement unit continues the measurement.

A printing apparatus includes an interface that supplies power from the outside, a battery, and a conveyance unit that conveys a printing medium using power from the battery or interface. When the remaining battery level before conveyance of a printing medium starts is determined as being not less than a first threshold, the conveyance unit is caused to convey the printing medium by power from the battery. When the remaining battery level is determined as being less than the first threshold and the printing apparatus is supplied with power from the interface, the battery is charged with power from the interface, the conveyance unit is caused to convey the printing medium, and a second determination is performed for the remaining battery level after the printing medium reaches a predetermined position. When the remaining battery level is determined as being not less than a second threshold, image-printing processing starts.

A print system includes a head, a conveyance motor, a first connector, and a second connector, a power supply circuit. When a first power source is connected to the first connector and a second power source is connected to the second connector, the power supply circuit supplies at least some of a first power to the head and supplies at least some of a second power to the conveyance motor. The first power is a power of the first power source. The second power is a power of the second power source.

A print system includes a head, a conveyance motor, a first connector, and a second connector, a power supply circuit. When a first power source is connected to the first connector and a second power source is connected to the second connector, the power supply circuit supplies at least some of a first power to the head and supplies at least some of a second power to the conveyance motor. The first power is a power of the first power source. The second power is a power of the second power source.

A printer includes: a housing with walls enclosing a compartment, and defining an adjacent media supply chamber; a cover coupled to an end of the housing beside the media supply chamber, movable between open and closed positions to expose or enclose the media supply chamber; a print head to apply indicia to media from the media supply chamber, and cooperate with the cover to form an outlet at a front wall of the housing for dispensing the media; a frame within the compartment, defining a first mounting surface beside and oriented towards a second end of the housing, a second mounting surface with a portion orthogonal to the first mounting surface and oriented towards a side of the housing, and a third mounting surface oriented towards the front wall; and first, second, and third antennas disposed on the first, second, and third mounting surfaces respectively.

A printer includes: a housing with walls enclosing a compartment, and defining an adjacent media supply chamber; a cover coupled to an end of the housing beside the media supply chamber, movable between open and closed positions to expose or enclose the media supply chamber; a print head to apply indicia to media from the media supply chamber, and cooperate with the cover to form an outlet at a front wall of the housing for dispensing the media; a frame within the compartment, defining a first mounting surface beside and oriented towards a second end of the housing, a second mounting surface with a portion orthogonal to the first mounting surface and oriented towards a side of the housing, and a third mounting surface oriented towards the front wall; and first, second, and third antennas disposed on the first, second, and third mounting surfaces respectively.

A printer for issuing print media includes: a rechargeable battery configured to supply power to the printer; a print unit configured to print information on the print media; a display unit; and a control unit configured to: compute A based on: a decrease in remaining battery capacity of the battery during a period of time from a reference time to the present time, and a total number of print media that have been issued during the period of time, where A is defined as remaining battery capacity of the battery decreased as a single print medium is issued; compute (BC)/A to obtain a number of print media on which the print unit can print, where B is defined as present remaining battery capacity, and C is defined as a lower limit of remaining battery capacity of the battery; and control the display unit to display the number of print media.

A wireless power transmission system includes a plurality of power transmitting antennas, a plurality of power receiving antennas, and a combiner configured to combine power transmitted to the power receiving antennas. At least one of a group of the plurality of power transmitting antennas and a group of the plurality of power receiving antennas is translated in a first direction relative to the other. During the translation, at least one of the power receiving antennas and at least one of the power transmitting antennas are coupled by one of an electric field and a magnetic field.