SUPERIMPOSED DATA READ CIRCUIT

摘要

PROBLEM TO BE SOLVED: To prevent an operation of a receiver side from causing a hindrance by outputting communication data to be outputted that are converted into invalid data when the logic of superimposed data has been changed by an external disturbance noise. SOLUTION: The circuit has an upper limit threshold 30 and a lower limit threshold 31 to detect an external disturbance noise 15. In the case a level of the external disturbance noise 15 has exceeded the upper limit threshold 30 or is less than the lower limit threshold 31, the circuit outputs communication data whose stop bit logic is forcibly reversed to a receiver so as to allow the receiver discriminates the received communication data to be invalid data.