Abstract: An adaptable programmable calculator employs modular read-write and read-only memories separately expandable to provide additional program and data storage functions within the calculator oriented toward the environment of the user, and an LSI NMOS central processing unit, which includes the capability of bidirectionally transferring information between itself and various input/output units. The input/output units include a keyboard input unit having a full complement of alphanumeric keys, a magnetic tape cassette reading and recording unit capable of bidirectionally transferring programs and data between the calculator and a magnetic tape, a 32-character solid state output display unit capable of displaying every alphabetic and numeric character.

Abstract: An adaptable programmable calculator employs modular read-write and read-only memories separately expandable to provide additional program and data storage functions within the calculator oriented toward the environment of the user, and an LSI NMOS central processing unit, capable of handling sixteen-bit parallel binary operations, binary-coded-decimal arithmetic, sixteen-bit parallel input/output operations, two-level interrupt from up to sixteen input/output devices, and a direct memory access channel.