| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a clock switching device which does not cause an instantaneous interruption adversely affecting a clock-receiving circuit when the clock is switched from one system to the other system. <P>SOLUTION: When a first switching signal 216 is inputted for the changeover of a system clock to an another system state monitoring part 232 inside the first clock supply function part 211 of an active system, a clock switching signal 245 is outputted. When interruption is detected in a clock interruption detection part 233, a clock interruption masking part 234 masks the clock, a clock low point detection part 239 detects the point in time at which each clock matches with the logical level of a side corresponding to pull-down resistance, and a switching timing generation part 242 generates a system switching timing and reports the switching timing to a state control part 249 and a standby system side. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
