| 摘要 |
<p>A data processor having a main processor and a coprocessor whose function is invalidated executes an operating system for a data processor having the main processor and the coprocessor, thereby performing context switch. Here, when a pre-decoder unit (30) detects that a coprocessor command is fetched, the main processor executes the coprocessor command by replacing it by commands (41-44) executing only operation for updating the values held by a general-purpose register and a program counter. This can guarantee the operation for the command using the general-purpose register and a program counter and normally operate the aforementioned operating system by the data processor having the coprocessor whose function is invalidated.</p> |
