| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent an unintended resetting of an operation mode when a microcomputer performing processes by a control program incorporates an input and output circuit having a plurality of operation modes. <P>SOLUTION: An operation mode control circuit includes, at least: a control signal generator; a write inhibit circuit which holds a second output signal from the control signal generator in response to a first output signal from the control signal generator, and generates a write signal according to the logical value of the held signal; and a control circuit for holding a third output signal from the control signal generator in response to the write signal. As the write signal corresponding to the logical value of the second output signal from the control signal generator, one is a signal whose logical value is fixed, and the other is the buffer signal of the first output signal from the control signal generator, the control signal is supplied to a selection circuit for selecting a signal generation circuit for transmitting the signal to the outside among a plurality of signal generation circuits at least including a data register circuit. <P>COPYRIGHT: (C)2009,JPO&INPIT |
