| 摘要 |
<p>PURPOSE:To exactly decide the cause of the start of a device by the aid of a simple constitution and at low cost by inputting a system reset signal and the internal reset signal of the device itself to a single flip-flop, and obtaining a hot line connection decision signal. CONSTITUTION:When the device is hot-line-connected, only the internal reset signal, the inverse of IRES is inputted to the flip-flop 1, and the flip-flop 1 comes to a set state, and the hot line connection decision signal STR comes to H-level. Besides, when a system power source is switched-in while the device being in the state that it is connected to an information processing system previously, the flip-flop 1 comes to a reset state, because of the difference of output time between the system reset signal, the inverse of SRES and the internal reset signal, the inverse of IRES, outputted from a power source rise-up monitor circuit 2, and the hot line connection decision STR comes to L-level. Thus, the cause of the start of the device can be easily and at low cost decided without accompanying the change of the circuit of a system side, etc.</p> |
