Abstract: A keyboard with N-key rollover has a matrix of key columns and lines for successively issuing key codes for depressed keys. When first and second keys on the same column are detected as being depressed and then a third key on the same line as one of the first and second keys is detected as being depressed, or when first and second keys on the same line are detected as being depressed and then a third key on the same column as one of the first and second keys is detected as being depressed, a key code for the third key or a key code for a fourth key detected in error upon depression of the third key are prevented from being issued.

Abstract: A control device for cooking apparatus includes an input panel for inputting a desired cooking condition. The input panel includes a flexible panel on which a plurality of cooking condition set key-patterns are formed in line. When a desired cooking condition set key-pattern is pressed, the input panel produces a voltage corresponding to the pressed key-pattern. The value of this voltage is changed step by step from one side key-pattern toward the other side key-pattern on the flexible panel.

Abstract: An object placed on a transparent touch panel horizontally arranged on a CRT is detected as an undesired material if a touch state longer than a normal key-in input time is detected. Removal of the undesired material is requested by the CRT display or an audio unit so that repetitive malfunction is prevented. A second longer time may be set to call a service man.

Abstract: A remote control system for a television receiver includes provisions for delaying a predetermined time duration before responding to a new remote control comman after a previous remote control command to prevent undesired toggling of toggle control functions (e.g., power application and muting) due to momentary interruptions of remote control transmissions which may occur when a user unintentionally points the transmitter away from the television receiver. It also includes provisions for sampling the envelope of the remote control transmission to determine if an interruption corresponds to an intended termination of transmission to provide rapid repeated response (i.e., "machine-gunning") to commands such as "channel up" or "channel down".

Abstract: A matrix keyboard system for producing key codes in response to the actuation of key switches. The keyboard system includes ghost key condition detection. In the keyboard system, a group of parallel drive lines and a group of orthogonal parallel sense lines form a matrix, with a key switch being associated with each of the intersection points on the matrix. The drive lines are sequentially activated, and the actuation of a key switch along an activated drive line results in the coupling of a drive signal to the associated sense line. A ghost key condition arises when three of the four corners of a notional rectangle in the matrix contain an actuated key switch. The ghost key condition detector senses the presence of drive signals not only on the sense lines but also on the drive lines, with a ghost key condition being identified if a drive signal is sensed on two or more sense lines and two or more drive lines simultaneously.

Abstract: An improved keyboard assembly is provided wherein a partition is positioned between adjacent keys and prevents an inadvertent simultaneous operation of two or more keys. The paartition can be advantageously utilized to control the cursor moving keys on a word processor keyboard thereby permitting the keys to be closely positioned adjacent each other while insuring only the desired key will be activated.

Abstract: An input device which can be employed to input commands to a computer directly through a CRT display is disclosed. The input device employs a plurality of infrared light emitting diodes and phototransistors aligned in individual emitter-detector pairs. Infrared beams from the emitter cross the display field before striking the corresponding detector. Emitters and detectors are sequentially activated and each emitter is pulsed or modulated at a frequency different from the variation of ambient conditions during each emitter activation interval. The detection circuitry thus can distinguish the varying emitter signal from ambient or spurious variations. A number of pulses at the pulsed or modulated emitter frequency would be detected unless an opaque element were blocking the particular beam.

Abstract: A keyboard having an encoder in the form of a microcomputer includes an automatic reset circuit and a key matrix circuit. The microcomputer constantly feeds a key scanning signal to the key matrix and to the automatic reset circuit. If a program used in the microcomputer gets out of control as by external noise, the key scanning signal is ceased. The automatic control circuit detects such stoppage of the key scanning signal that extends over a given period of time, and the circuit then supplies a reset signal to the microcomputer to automatically restart it from the beginning of the program.

Abstract: A multiplex system includes a master controller and a plurality of remote stations which are connected together by a cable. The cable is a twin co-ax cable which includes data and clock conductors which are surrounded by power and ground conductors. The power and ground conductors are capacitively coupled such that the power conductor simultaneously transmits power and provides an effective shield. The master controller includes a microcomputer which in turn includes an UART. The UART is used to transmit command bits to the remote stations while the CPU reads response bits from the remote stations in order to allow response bits to be interleaved in time with command bits. In one embodiment, the command bits are used to strobe row conductors of a keyboard and the response bits are used to monitor column conductors of the keyboard to allow a keyboard to be controlled by the master controller 20 in a simple and efficient manner.

Abstract: A matrix switching apparatus for preventing a pseudo input condition caused by a detour of a signal as well as output of an erroneous signal caused by a noise intruding into an apparatus and the like, in which a plurality of key lines having a plurality of switches are arranged in the first and second directions respectively. The apparatus includes a detector for detecting an ON condition of the plurality of the switches by a time-sharing detection, a counter for counting up a number of the switches which are in the ON condition simultaneously, both totally and respectively with the key lines, a storage means for storing a first, second, third and fourth statuses which represent the condition of the switches respectively, and a controller for inverting the second status into the first status.