| 摘要 |
PURPOSE:To lighten the burden of a CPU so as to improve the processing capacity of the CPU, by providing a function which exclusively occupies a serial interface in an input-output device and another function which performs poling processes to other input-output device. CONSTITUTION:An exclusively occupying signal accepting part 11, driving part 12, and poling processing part 13 are provided in a CPU 1. The exclusively occupying signal accepting part 11 accepts exclusively occupying signals from required input-output devices and stops and actuates the driving part 12 in accordance with the exclusive occupy requesting signal and exclusive occupy ending signal of input-output devices. When the driving part 12 is stopped, the poling processing part 13 of the CPU 1 stops the poling process and, when the driving part 12 is actuated, the poling processing part 13 performs poling processes. An exclusively occupying signal receiving and transmitting part 21 and poling processing part 22 are provided in a required input-output device, for example, device 2-1, and the part 21 and 22 respectively perform sending out of exclusively occupying signals and receiving of answer signals to and from the CPU 1 and poling processes upon receiving 'yes' signals, when its own device exclusively occupies a serial interface. |
