| 摘要 |
PURPOSE:To prevent the drop of CPU's processing ability by interrupting the execution of a program according to a request arising at the time of receiving an audio CMT input pulse and receiving and processing pulse data on the CMT by the CPU itself. CONSTITUTION:When a reception I/O is requested, an I/O request reception part 601 detects a reception I/O processing execution request line 603, and simultaneously samples the level of an I/O processing execution mode specifying line 604. When it is at a high level, the I/O request reception part 601 judges that the request is a CMT pulse data reception processing request, and sets forcibly a CMT pulse data reception processing code to a command register 702. An execution control part 704 inhibits the address update of a program counter 101-1, and processes a series of work while values of the program counter 101-1, a program status work 101-2 and a general-purpose register set 101-3 are held. Thus the time required for return from the interruption can be substantially reduced, and the drop of CPU processing ability can be minimized.
|
