| 摘要 |
PURPOSE:To find and recover a fault in a short time, by confirming that a processor or a system device does not use the bus to select individual busses of the system bus and by comparing the potential of the selected bus with a prescribed potential. CONSTITUTION:A signal receiving circuit SRC consists of a multiplexer MPX, a comparator CMP1, a FF circuit FF, and a register CRG which controls them, and a signal transmission circuit STC which transmits signals to a system bus SBU consists of a register ORG and a driver BDR. A processor CPU is connected to a bus MBU which is connected to circuits SRC and STC, and a lighting circuit LDR provided with indicator lamps Lr, Le, and L0-Ln and a comparator CMP2 for power source check are provided. Individual busses of the system bus SBU are selected by confirming that the CPU, etc. do not use the bus MBU, and the potential of these busses is compared with a prescribed potential by the comparator CMP2, thereby finding and recovering a fault in a short time. |
