| 摘要 |
PURPOSE:To improve the conversion ability from a mechanical instruction to a micro-module by scaling down an instruction decoding programmable logic array (PLA) so as to simplify coding. CONSTITUTION:The instruction decoding PLA10 decodes contents of an instruction register 1 and outputs only discrimination information to the 1st table pointer register 11. Contents of the 2nd table pointer register 12 are subjected to increment, whereby the micro-module corresponding to one mechanical instruction is sequentially specified. Accordingly the PLA10 need not output directly the stored top address of each micro-module and updates the micro-module neither. As a result the PLA10 can be scale down, and the coding can be simplified. |
