| 摘要 |
PURPOSE:To shorten a processing time with a semiconductor IC by providing plural ROMs having their address inputs connected in common to each other to store the 1st and 2nd digit addresses in the 1st and 2nd ROMs respectively and so on, and sending each output to an arithmetic circuit. CONSTITUTION:The data are outputted from the ROM 1,2 and 3 with decision of a row address and the digit address inputs 1,2 and 3 and then inputted to an arithmetic circuit 4. The circuit 4 can perform the OR, the AND, the addition, the subtraction, the multiplication, etc., and outputs these arithmetic results as the arithmetic outputs. When the inputs 1-3 show L11, L21 and L23 respectively, the data to be computed show the digits, i.e., N=1, N=2 and N=3. Meanwhile the data to be computed are shown in the digits N=7, N=5 and N=3 with the inputs 2 and 3 equal to L22 and L31 respectively. These data are outputted from the ROM 1-3. Thus just a single reading operation suffices read of the ROM, therefore the processing time is shortened. |
