INTERRUPTION CONTROLLING CIRCUIT

PURPOSE:To easily tranfer data from an external device, and also to execute an interruption response at a high speed, by constituting so that transfer data in the regular mode and refeence data in the interruption mode can be transferred to the side of a microprocessor. CONSTITUTION:A control word is set to a programmable peripheral interface PPI 5 from a master processor 1. In case when the processor 1 tranfers data to an external device 4, a device number is outputted to an address bus, transfer data is sent out to a data bus, and a data write signal WR is supplied to the PPI 5. The transfer data is stored in the PPI 5, the device 4 reads this data by the interruption response processing, and one data transfer ends. In case when the device 4 executes interrption to the processor 1 side, the device 4 sends out reference data to an output terminal of the data bus, the PPI 5 stores it. The processor 1 reads this reference data by the interruption response, and executes the processing corresponding to contents of an interruption request in accordance with said reference data.