Communication anomaly detecting device, and passenger detecting device

Abstract

An information request portion receives an information request signal transmitted to an information response portion at its own receiving port. The information request portion comprises at least either a power supply system anomaly determination portion or a ground anomaly determination portion. The power supply system anomaly determination portion determines a short-circuit between a signal line and a power supply system in a case where the information request signal received at the receiving port is always fixed to a H (high) level. The ground anomaly determination portion determines a short-circuit between a signal line and a ground in a case where the information request signal received at the receiving port is always fixed to a L (Low) level. Consequently, the anomaly region of the signal line connects the information request portion and the information response portion so that bidirectional digital communications are possible or the cause of the anomaly is specified.

1 . A communication anomaly detector of a communication system, comprising an information request portion having a receiving port, at least one information response portion connected to the information request portion in such a manner that bidirectional digital communications are possible through a signal line, and a power supply system, wherein, when the information request portion transmits an information request signal, the information response portion receives the information request signal and transmits an information response signal to the receiving port of the information request portion,
 the information request portion, when transmitting the information request signal to the information response portion, receiving the information request signal at the receiving port, and the information request portion comprises at least one of a power supply system anomaly determination portion and a ground anomaly determination portion, the power supply system anomaly determination portion determining a short-circuit between the signal line and the power supply system in a case where the information request signal received at the receiving port is always fixed to a high level, and the ground anomaly determination portion determining a short-circuit between the signal line and a ground in a case where the information request signal received at the receiving port is always fixed to a low level.   
   
   
       2 . The communication anomaly detector according to  claim 1 , wherein the information request portion comprises a signal line/ground line anomaly determination portion for determining that the signal line is opened or that a feeding ground line to the information response portion is opened in a case where the information request signal transmitted to the information response portion is the same as the information request signal received at the receiving port, and the information response signal received at the receiving port from the information response portion is always fixed to a high level. 
   
   
       3 . The communication anomaly detector according to  claim 1 , wherein the power supply system anomaly determination portion determines a short-circuit between the signal line and the power supply system when a state is repeated for a predetermined number of times, in which state the information request signal received at the receiving port is fixed to a high level during the entirety of a predetermined communication period comprising a request period during which the information request portion transmits the information request signal and a response period for awaiting reception of the information response signal from the information response portion. 
   
   
       4 . The communication anomaly detector according to  claim 1 , wherein the ground anomaly determination portion determines a short-circuit between the signal line and the ground when a state is repeated for a predetermined number of times, in which state the information request signal received at the receiving port is fixed to a low level during the entirety of a predetermined communication period comprising a request period during which the information request portion transmits the information request signal and a response period for awaiting reception of the information response signal from the information response portion. 
   
   
       5 . The communication anomaly detector according to  claim 1 , wherein the information request portion is an electronic control device, and the information response portion is a load sensor for acquiring the load information according to a load applied to a seat, and the communication system constitutes an occupant detector, wherein, when the electronic control device transmits the information request signal, the load sensor receives the information request signal and transmits the load information signal as the information request signal to the receiving port of the electronic control device, and the electronic control device receives the load information signal, thereby performing an occupant determination.