| 摘要 |
PURPOSE:To eliminate an interruption address register and to miniaturize a device, by using an interruption scanning counter for the storage of an interruption address. CONSTITUTION:Interruption request lines S11 and S12-S1n are connected to an interruption selecting circuit 21, and an interruption request line corresponding to an output S5 of an interruption scanning counter 23 is selected. The state of the selected request line is stored successively in an interruption detecting circuit 22. On the other hand, an address scanning counter 24 counts the addresses of transmission data by a transmission clock. Then the count value of the counter 23 is stopped at an interruption address corresponding to the interruption request line in case an interruption is given from the circuit 22 immediately before the final timing of the transmission data address. With the final timing of the transmission data address, an address switching circuit 25 switches the output address to the output of the counter 23 from the output of the counter 24. |
