Abstract: A function of write protection against careless writing in a memory card is realized by means other than a mechanical switch. Existing address lines exceeding the capacity of a memory and an existing write control line are used as inputs to a gate circuit so that data can be written in the memory only in the case where a specific value can be decoded. Accordingly, a write address space is limited to a specific address space other than the lowermost address space. Accordingly, data cannot be written if the specific address space cannot be known. As a result, the function of write protection can be provided without using any switch and without introducing any nonstandardized terminal and any control signal.

Abstract: A memory card having a printed circuit board mounted with semiconductor elements and provided with terminal portions along one side thereof and a card basic board formed with a broad recess on the lower surface thereof for receiving said printed circuit board therein. Void contact spaces are provided along one side thereof. The card basic board is formed with upper openings for communicating with the contact spaces on the upper surface of the card basic board and with inserting ports for communicating with the contact spaces on a side surface of the card basic board. Upper beams are provided between the upper openings and the corresponding inserting ports, and lower beams are provided near the inserting ports.

Abstract: An alkaline cell comprising a positive electrode can for accommodating positive active materials formed from stainless steel containing more than 23% chrome by weight for preventing the positive electrode can from being damaged in gastric juice. The stainless steel may be coated with nickel prevent the release of Cr.sup.6+ ions into electrolyte of the cell.

Abstract: A portable memory cartridge includes a mass memory, a data bus, an address bus, control signal lines for carrying signals for making access to the mass memory, a password memory for storing a flag indicating the inhibition of read/write access to the mass memory, a password memory for storing a particular authorized password, and a comparator for comparing an input password with the particular password set previously. Whe the comparison results in coincidence, a control signal required for the access is supplied to the mass memory for enabling the access to the mass memory in data read or write mode or data read and write mode.

Abstract: Disclosed is a composite memory device which comprises a recording disc medium having a large number of recording tracks to and from which data is written and read, a housing for holding the recording disc medium, a rewritable semiconductor memory disposed within a portion of the housing, and pins disposed within a portion of the housing for transferring data between the semiconductor memory and an external device.