PURPOSE:To continuously output a normal control signal to respective types of the load without system-down even at the time of the abnormality of an output circuit by providing plural selectable output circuits, and when the abnormality occurs at a control signal outputted, changing them over to a normal output circuit immediately. CONSTITUTION:When the output of an interface 6 is outputted to an output circuit 7A by a block selecting circuit 12, the control signal of the output circuit 7A is inputted through an input circuit 10A to a data collating circuit 13. A data collating circuit 13 collates the input data and the output data of the interface 6, and when both are not coincident, it is judged that some abnormality occurs at the output circuit 7A, and the block changing-over command is outputted to the block selecting circuit 12. The block selecting circuit 12 automatically changes over a block 11 used from 11A to 11B and the output signal of the interface 6 is outputted to an output circuit 7B.
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