Abstract: Disclosed is an electric power generation device comprising: a pair of electrodes arranged opposite to each other; and an electret member that is arranged between the pair of electrodes to be spaced apart from the pair of electrodes, and is provided to be movable in a direction of a perpendicular axis passing through the pair of electrodes.

Abstract: Disclosed is an electric power generation device comprising: a pair of electrodes arranged opposite to each other; and an electret member that is arranged between the pair of electrodes to be spaced apart from the pair of electrodes, and is provided to be movable in a direction of a perpendicular axis passing through the pair of electrodes.

Abstract: A data processing apparatus has a central processing unit. The CPU causes a memory to store for example input sales data in units of department sales and other items. When a power supply is turned off, a battery supplies back-up power supply voltage to the memory to retain the storage contents of the memory. When the output voltage from the battery is decreased to a value which disables back-up of the memory, is latch circuit is set. The latch circuit is held in the set state until it is forcibly reset. Even if the power source is turned on again, the CPU inhibits sales data input to the electronic register in response to an output signal from latch circuit, thereby preventing errors in the electronic register caused by invalid data in memory.

Abstract: An electronic cash register for printing designated data includes a keyboard having a plurality of keys. The keyboard has a switch for designating a write-in mode and a read-out mode and a plurality of keys including ten keys, function keys, etc. The data coupled by the operation of these keys are stored in the journal memory. The data to be read out in the read mode are stored in a register included in a CPU. The CPU performs a comparison of the data from the journal memory and the designated data read out from the register in the CPU in its calculating section and, when the compared data coincide, the read-out designated data are output for display in a display section or printing in a printing section.