| 摘要 |
PURPOSE:To attain rapid switching of a general register bank by forming a bank identification area storing bank identification data for specifying plural general register banks which can be switched and used in a program counter. CONSTITUTION:The bank identification (ID) area Ebr storing the bank ID data for selecting a prescribed register bank out of the register banks RB1-RB8 is formed in the program counter PC and the bank ID data are included in vectors stored in the program counter PC. Since the register bank an be switched only through vectoring of the program counter PC, a memory cycle is required only at the time of receding the program counter PC, the number of processing steps can be reduced and the switching of the register bank can be rapidly executed. Consequently, multi-task processing based upon interruption can be rapidly attained. |
