| 摘要 |
PURPOSE:To attain miniaturization by dividing an n bits into plural blocks, decoding each divided block tentatively and decoding a data word based on the combination of results to decrease the capacity of a ROM. CONSTITUTION:The code word unit is kept for a recovered code word by a serial/parallel converter 1 and a 12-bit D flip-flop 2(DFF) at first. Then the head bit of the code word stored in the DFF2 is fed to one input of an exclusive OR gate 4 via an inverter 3 and an output of the DFF2 is given as it is to the other input. Then the high-order and low-order 6 bits in the code word of a table pattern appearing at the output terminal of the gate 4 are given respectively to the address terminal of ROMs 5, 6. Finally, a 2-bit value R1 being an output of the ROM5 and a 4-bit value R2 being an output of the ROM6 are given to a ROM7, then a data word corresponding to the inputs R1 and R2 appears and it is an output of the decoder.
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