Patent ID: 9560181
Date: 2017-01-31
CPC Classifications: H04M

Claim:
1. A communication apparatus accepting connection of a telephone and connecting to a telephone line, the communication apparatus comprising: a memory storing a program; at least one processor which executes the program stored in the memory; a line connection terminal configured to connect the communication apparatus to the telephone line; a telephone connection terminal configured to connect the communication apparatus to the telephone; a modem provided on a connection path between the line connection terminal and the at least one processor; a connection relay configured to switch between connection and disconnection of the telephone connection terminal to and from the modem wherein the at least one processor executes first determination for determining whether a first voltage of the connection path under conditions where the telephone connection terminal is connected to the modem is greater than or equal to a first threshold value if the at least one processor determines by the first determination that the first voltage is greater than or equal to the first threshold value, the at least one processor executes second determination for determining whether a second voltage of the connection path under conditions where the telephone connection terminal is disconnected from the modem tends to decrease; and the at least one processor executes third determination for determining connection states of the telephone connection terminal and the line connection terminal based on a determination result of the first determination and a determination result of the second determination, wherein, if the at least one processor determines by the second determination that the second voltage has decreased more than once, it is determined by the third determination that a wrong connection has been made.