| 摘要 |
PURPOSE:To improve the execution performance of a microprogram by using an immediate data part effectively. CONSTITUTION:When a microinstruction word is read out from a control storage 10 to a microinstruction register 30 and executed, data A are inputted from a working register 60 to a shifter 61 and the exceptional condition of the data A is reflected to a flag 62 because a submicroinstruction part 307 instructs the input of the data A. When a microinstruction word in an updated address is read out and executed, the exceptional condition of the data A is decided by a condition deciding part on the basis of a flag 62 because the instruction part 307 indicates the input of data B, and an exceptional code 55H in the immediate data part 306 is stored in an exceptional code register 42. When a microinstruction word is read out and executed, the exceptional code 55H stored in the register 42 is not updated and the exceptional condition of the data B is decided by the circuit 40 on the basis of the flag 62.
|
