| 摘要 |
<p>PURPOSE:To shorten a processing time without performing complicate arithmetic by allocating various variable signals to address bit columns of an ROM, and storing digital data determined through the allocation according to combinations of addresses corresponding to constituent addresses. CONSTITUTION:When the number of bits of an address bit line of the ROM used for the data table system of the ROM is p+q, one variable X is allocated to the high-order (p) bits of the address bit column and the other variable Y is allocated to the low-order (q) bits. Further, specific data values corresponding to combinations of respective values of those variables are stored previously in addresses indicated by address signals based upon the allocation combinations of corresponding variable values. When data X=Xn and Y=Yn are inputted, a data value Fnn is read out of an address corresponding to an address signal XnYn as an answer corresponding to the combination of both values Xn and Yn. When X=Xm and Y=Ym are inputted, a corresponding data value Fmm is read out to shorten the processing time.</p> |
