| 摘要 |
PROBLEM TO BE SOLVED: To provide a portable telephone set with an inexpensive and simple configuration to select the operating mode in response to a kind of a connected accessory. SOLUTION: Accessory type information denoting whether a connected accessory is a hand-free circuit 12 or a data transmission circuit 13 is stored in a nonvolatile memory of a portable telephone set 11, and the operating mode of the portable telephone set 11 is automatically switched based on the presence of connection of an accessory to the portable telephone set 11 and the accessory type information stored in the nonvolatile memory of the portable telephone set 11. |
