| 摘要 |
PURPOSE:To prevent the increase in frequency of error of each decorder itself, by enabling to check a failure of an instruction type decorder and an operand type decorder itself, through the provision of a specific type check circuit section. CONSTITUTION:The next instruction is pre-fetched to a register 2, and the instruction type and the operand type of the next instruction decorded with an instruction type decorder 3 and an operand type decorder 4 of a next instruction code interpreting section 1 are introduced to a page cross detector 5 to check if the page cross is caused at the next instruction. A data processor with this constitution is provided with a type check circuit section 6 relating to the next instruction constituted so that the state of combination not permitted mutually or permitted can be detected based on the said decorded instruction type signal and the operand type signal, e.g., having the content as shown in figure. |
