| 摘要 |
PURPOSE: To detect the presence or absence of attachment attached to a main body without providing parts such as a switch and the like. CONSTITUTION: When the power source of a device A 501 is turned on in a state where a user detaches a device B 502 (that means, a connector 100 is detached) in order to perform some processing, a power source line 503 rises so as to try to supply power to the device B 502. However, a current (It) does not flow to a resistor 504, a power supply detecting device 505 detects the same voltage as that of the power source line 503 as Vs, and outputs a High signal, for instance, to a CPU. Therefore, the CPU performs ordinary operation by judging that the device B 502 is attached when the output signal from the device 505 is Low. |
