System for transferring data between central units and controlled units

Claim 1

A system enabling the transfer of data between central units and controlled units comprising at least two central units, a plurality of groups of controlled units, a plurality of peripheral units including one peripheral unit per group of controlled units and per central unit, means connecting said peripheral unit to receive orders from the central units and retransmit them to the controlled units; means linking the two central units including an information-transmission link, each central unit including central control circuits, each central unit including a first storing device for each peripheral unit assigned to the central unit for storing information indicating whether the corresponding periperal unit is accessible by the central unit or not; whereby when a central unit is preparing to transmit an order to a peripheral unit, the central control circuits read the information provided by the first storing device corresponding to the peripheral unit and, according to the read information, control either the transmission of the order directly to the peripheral unit, or the transmission to the other central unit, through the transmission-link, of a message containing the order and the identity of the peripheral units, each central unit including a second storing device for every periperal unit assigned to the other central unit for storing information indicating whether the other central unit has access to that peripheral unit; means arranged so that when a central unit has an order to transmit to a group of controlled units, but lacks access to its peripheral unit, the central control circuits read the information contained in the second storing device corresponding to the analogous peripheral unit of the other central unit and, according to the read information, they enable the transmission of the order to the other central unit, through the transmission-link, each central unit including a third storing device for every peripheral unit assigned to the central unit for storing characteristic information when the central unit transmits, for the account of the other central unit, an order to the peripheral unit; the central control circuits examining, at the end of the execution of an order by the peripheral, the information contained in the third storing device, which will then enable it to determine whether the order has been executed for its own account or for the account of the other central unit; and, in this latter case, the central control circuits transmit to the other central unit, through the transmission link, a message informing of the end of execution of the order.

Claim 2

A system enabling the transfer of data between central units and controlled units comprising at least two central units, a plurality of groups of controlled units, a plurality of peripheral units including one peripheral unit per group of controlled units and per central unit, means connecting said peripheral unit to receive orders from the central units and retransmit them to the controlled units; means linking the two central units including an information-transmission link, each central unit including central control circuits, each central unit including a first storing device for each peripheral unit assigned to the central unit for storing information indicating whether the corresponding periperal unit is accessible by the central unit or not; whereby when a central unit is preparing to transmit an order to a peripheral unit, the central control circuits read the information provided by the first storing device corresponding to the peripheral unit and, according to the read information, control either the transmission of the order directly to the peripheral unit, or the transmission to the other central unit, through the transmission-link, of a message containing the order and the identity of the peripheral units, each central unit including a second storing device for every periperal unit assigned to the other central unit for storing information indicating whether the other central unit has access to that peripheral unit; means arranged so that when a central unit has an order to transmit to a group of controlled units, but lacks access to its peripheral unit, the central control circuits read the information contained in the second storing device corresponding to the analogous peripheral unit of the other central unit and, according to the read information, they enable the transmission of the order to the other central unit, through the transmission-link, each central unit including a third storing device for every peripheral unit assigned to the central unit for storing characteristic information when the central unit transmits, for the account of the other central unit, an order to the peripheral unit; the central control circuits examining, at the end of the execution of an order by the peripheral, the information contained in the third storing device, which will then enable it to determine whether the order has been executed for its own account or for the account of the other central unit; and, in this latter case, the central control circuits transmit to the other central unit, through the transmission link, a message informing of the end of execution of the order.