| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device that can achieve desired bus communicating actions irrespective of whether a pull-up resistance is connected to a bus line or not, and a bus connection method for the same. <P>SOLUTION: A semiconductor device includes: external pull-up judging means that applies a pull-down voltage to a bus line via an internal pull-down resistance and judges the presence or absence of connection of an external pull-up resistance outside the semiconductor device to the bus line, according to the voltage level of the bus line at the time of application of the pull-down voltage; and internal pull-up setting means that, when it is judged that no external pull-up resistance is connected to the bus line, stops application of the pull-down voltage, applies a pull-up voltage to the bus line via an internal pull-up resistance and, when it is judged that an external pull-up resistance is connected to the bus line, stops application of the pull-down voltage. <P>COPYRIGHT: (C)2012,JPO&INPIT |
