| 摘要 |
PURPOSE:To process data having accuracy of two-word quantity without changing the bit width of the data value, by providing a double-accuracy processing and controlling unit which processes double-accuracy data composed of continuous two words together with a processor unit. CONSTITUTION:In the case of the operation of data which requires the accuracy of two-word length, the data are given to this device after dividing them into continuous two words and a bit which indicates that the data are to be processed in the unit of the two words with double accuracy is given to the first one of each two words. Each data circulate the ring bus of the device and are successively calculated by a processor unit 6, but, when it is indicated that the data and continuous data are of double accuracy by the bit of the data, calculated results of the first word which are necessary for calculating the next coming second word are given through a double-accuracy processing and controlling unit 7 which holds the internal state of the processor unit 6 and double-accuracy calculation is executed. Therefore, processes by double- accuracy data can be executed while the bit width and function of conventional data value are maintained. |
