| 摘要 |
PROBLEM TO BE SOLVED: To easily detect whether or not a main substrate and sub substrates are connected normally. SOLUTION: When sub substrates 4a, 4b,...4n are connected normally to connectors 2a, 2b,...2n provided on the main substrate, a predetermined voltage signal is outputted to ground lines of the sub substrates 4a, 4b,...4n. When any one of the sub substrates 4a, 4b,...4n is not connected normally to the connectors 2a, 2b,...2n, a predetermined voltage signal is outputted as a detection signal from an output terminal To. By this construction, whether or not the connectors 2a, 2b,...2n are connected normally to the sub substrates 4a, 4b,...4n can be judged. |
