| 摘要 |
PURPOSE:To increase arithmetic processing speed by performing both upper and lower 16-bit arithmetic processings independently of each other and in parallel with each other together with the arithmetic processing of the 32-bit data. CONSTITUTION:When the arithmetic processing is carried out with the 32-bit data, the arithmetic instruction of the 32-bit data given from outside via a control instruction line 17 is applied to ALU parts 14-1 and 14-2 via a lines 19a and 19b after the decoding 18 of a control instruction. These ALU parts 14-1 and 14-2 perform the arithmetic processing by means of the output data of latch parts 12a-12d selected by data source selection parts 13a-13d and upper and lower 16-bit data given from external input data lines 15a-15d. In a 16-bit arithmetic processing mode, a 16-bit arithmetic instruction given via the line 17 is decoded 18 and applied to the parts 14-1 and 14-2. These ALU parts use the output data of the selected latch part and the 16-bit data given from lines 15a-15d to perform independently the upper and lower 16-bit operations. |
