Abrégé

A control/monitor signal transmission system according to the present invention comprises a plurality of slave stations that deliver and receive data by start-stop synchronization via a transmission line shared with a control-side device. A start signal for initiating synchronization is transmitted from the control-side device via the transmission line. The control-side device and each of the slave stations locally and internally generate a virtual transmission clock based on the start signal. The period from the end of the start signal to the beginning of a subsequent start signal is divided in time into a plurality of periods corresponding to one cycle of the virtual transmission clock. The one cycle of the virtual transmission clock is divided in time into a first set period and a second set period. Data is extracted on the basis of a difference in current value between the first set period and the second set period.

Classes IPC  ?

• H04L 12/40 - Réseaux à ligne bus

Abrégé

The present invention comprises: a control unit; a master station that performs data transmission/reception; and a plurality of slave stations that perform, according to a transmission synchronization scheme, data transmission/reception with the master station via a common transmission line. The slave stations superimpose, onto a power source voltage area of a transmission signal formed by connecting a plurality of power source voltage level pulse signals, a single current signal for which a prescribed level is maintained for a prescribed time with a current value allocated from a plurality of predetermined weightings representing a plurality of preset channels. The master station uses, as a reference value, the current value of the power source voltage area of an address-less region which has not been allocated for the transmission/reception of data in the transmission signal, and on the basis of the weightings and the difference between the current value of the current signal and the reference value, extracts, for each of the plurality of channels, a plurality of data pieces output to the same area of the transmission signal. The reference value is updated every time there is a transmission involving the address-less region.

Classes IPC  ?

• H04Q 9/00 - Dispositions dans les systèmes de commande à distance ou de télémétrie pour appeler sélectivement une sous-station à partir d'une station principale, sous-station dans laquelle un appareil recherché est choisi pour appliquer un signal de commande ou pour obtenir des valeurs mesurées
• G08C 15/08 - Dispositions caractérisées par l'utilisation du multiplexage pour la transmission de plusieurs signaux par une voie commune successivement, c.-à-d. utilisant la division de temps les signaux étant représentés par l'amplitude de courant ou de tension dans la voie de transmission
• H04B 3/54 - Systèmes de transmission par lignes de réseau de distribution d'énergie

Abrégé

The present invention is provided with: a master station which transmits and receives data to and from a control unit; and a plurality of slave stations which transmit and receive the data to and from the master station in a transmission synchronization scheme through a common transmission line, wherein a first area and a second area are provided in a power supply voltage area of power supply voltage levels in a transmission signal in which voltage pulse signals of a plurality of the power supply voltage levels are connected. The slave station superposes a single current signal, which has a prescribed level maintained for a prescribed period, onto either of the first area or the second area, and the master station extracts the data on the basis of a current value difference between the first area and the second area.

Classes IPC  ?

• H04Q 9/00 - Dispositions dans les systèmes de commande à distance ou de télémétrie pour appeler sélectivement une sous-station à partir d'une station principale, sous-station dans laquelle un appareil recherché est choisi pour appliquer un signal de commande ou pour obtenir des valeurs mesurées