Abstract: A slave-type interface circuit which can receive signals from a bus if the coding A.sub.0, A.sub.1 and A.sub.2 of its inputs S.sub.0, S.sub.1 and S.sub.2 corresponds to that mode of operation. The signals from the bus are then delivered to the inputs L.sub.1 and L.sub.2. With another mode of operation the coding of inputs S.sub.0, S.sub.1 and S.sub.2 corresponds to off-line operation on the basis of logic levels applied to the same inputs L.sub.1 and L.sub.2. A branching block (SBL) directs the signals from the inputs L.sub.1 and L.sub.2 either to a bus receiver RBUS or directly to a decoder CDEC controlling a group of switches (COM). In the case of operation with a bus, the bus receiver (RBUS) controls the logic for the progress for operations.