Programmable calculator to use magnetic strips were the HP-41C and TI-59. Continuous memory does not lose its content when the calculator is switched off. With continuous memory the user can, for example, change batteries without losing the entered programs. Compact Cassettes offered a simple, inexpensive alternative to magnetic cards. Usually, an interface module, such as the Casio FA-1, was used to connect the calculator to an ordinary cassette recorder and digital data were encoded as frequency-shift keyed audio signals. Sharp and Hewlett-Packard also sold dedicated micro- or mini-cassette recorders that connected directly to the calculator. These set-ups, while being more practical and
NCR Corporation 1953, the company acquired the Computer Research Corporation (CRC), after which it created a specialized electronics division. In 1956, NCR introduced its first electronic device, the Class 29 Post-Tronic, a bank machine using magnetic stripe technology. With the General Electric Company (now known as GE ), the company manufactured its first transistor-based computer in 1957, the NCR 304. Also in the 1950s NCR introduced MICR (magnetic ink character recognition) and the NCR 3100 accounting machines. In 1962, NCR introduced the NCR-315 Electronic Data Processing System which included the CRAM storage device, the first automated mass storage alternative to magnetic tape