| 摘要 |
PURPOSE:To improve the reliability by using a direct interruption circuit when an abnormality takes place in an hierarchy of closest high-order to apply interruption to the hierarchy of the closest high-order thereby attaining an abnormality restoration processing and the restoration processing from the hierarchy of low-order. CONSTITUTION:If an abnormality takes place in an intermediate adaptor 20, a CPU11a of a printer controller 11 supervises this state for a prescribed time, issues a non-maskable interrupt (NMI) so as to trigger an NMI circuit 14. The circuit 14 gives an NMI signal to the CPU20a of the adaptor 20 so as to attain a forcible interruption. Then the CPU20 is reset. Then the CPU20a executes an IPL program of an ROM5 and applies down-load of the control program again from the host CPU4. Thus, the CPU20a executes the control program on the RAM6 loaded newly. As a result, the adaptor 20 is restored normally. |
