Kabushiki Kaisha Daini Seikosha

Seiko Instruments & Electronics Ltd.

Yosuke Yoshida

Kazuhiro Asano

Masao Ishizaki

Kazuhisa Takazawa

Yasuo Sakami

Junichi Tsubouchi

Yoichi Fujioka

A data stored display device such as wrist watch comprises a central processing unit, a transmitting and receiving means for transmitting and receiving data and including a coil, RAMs written in and read out data under the control of the central processing unit, a display panel for displaying data stored in the RAMs and a stand-by switch for changing the transmitting and receiving means for non-transmitting and receiving condition to a transmitting and receiving condition so that the data stored display device can be inputted data from an external controller such as a computer having a transmitting and receiving coil and can function as a display panel of the external controller.

Data stored display device

A test circuit for watch IC capable of setting an operating mode with the operations of a plurality of switches has a ROM for deciding next operating mode in response to the outputs of said switching circuit including the switches and the outputs of flipflips for holding a present operating mode. A signal from a test terminal sets an initial state and provides the predetermined data instead of the outputs of flipflops to the ROM whereby an operator can set an arbitrary operating mode readily in a short time.

Test circuit for watch LSI

In an LSI for an electronic watch having a ROM and a RAM, the content of the RAM is rewritten by the interpretation and execution sequentially for time counting control and other controls. The address designation method of the ROM comprises a Program Counter Method for designating the next instruction address to be executed by a program counter and for numerical computation, and a Next Address Designation Method for designating directly by a fixed field value in an instruction and for the software for the watch. The two methods are employed selectively by the kind of instructions so that an emit-field may be used for other purposes such as the operation of a value which extends over several words of the RAM as a single instruction.

Electronic timepiece having address designation circuits of ROM and RAM

Growing community of inventors

Tokyo, Japan

Yosuke Yoshida