DATA TRANSFER CONTROL UNIT AND DATA TRANSFER CONTROL METHOD APPLIED TO THE SAME UNIT

摘要

PROBLEM TO BE SOLVED: To make normal transfer and arithmetic transfer efficient without making circuit constitution large in scale or complicated by performing control for transferring the arithmetic result of an arithmetic processing means as output data by a data transfer control means at the time of the arithmetic transfer. ;SOLUTION: A logical operation circuit 24 is a circuit which performs multi- input logical operation, and inputs respective data stored in data buffers 23A to 23C and outputs three-item exclusive OR(EX-OR) operation result to a selector 25. A flag control part 26 controls input and output of flag information of data transfer control parts 20A to 20C and has a function for switching the normal transfer and arithmetic transfer according to a switching signal TS. The switching signal TS is outputted from a CPU 5 as an input/output controller. In this case, the data transfer control parts 20A to 20C have a function for inputting and outputting flag information showing a data transfer state corresponding to read access and write access.;COPYRIGHT: (C)1998,JPO