| 摘要 |
PROBLEM TO BE SOLVED: To enhance functional extendibility of electronic equipment by making a memory card slot possible to be shared by a memory card and a USB device card. SOLUTION: Not only an SD memory card 21 but an SD USB card 22 as an I/O card in the same shape as the SD memory card 21 can be inserted into an SD slot 13 as a memory card insertion slot. A pull-down register for detecting device is provided on the side of the SD USB card 22. Thus, data lines D1, D2 are used as a pair of differential signals (D+, D-) in USB specification without influencing the data lines D1, D2 themselves, detection of the SD USB card 22 and USB data transfer by a USB host controller (USB HC) 122 can be performed. Consequently, the same slot can be shared between the SD memory card 21 and the SD USB card 22. |
