| 摘要 |
<p>PURPOSE:To attain small scale of the circuit through the use of circuits used in common by arranging a selector circuit corresponding to each incoming transmission line in the exchange system using a self routing channel and using the other circuits in common. CONSTITUTION:In the case of detecting the presence of a fault through the diagnosis of a channel, test drive information 14 is sent to a self-routing channel fault detection,circuit externally. A 1st AND circuit 15 receives the information 14 and an output 13 of an idle packet detection circuit 12 and brings the output 18 to an H level only when an idle packet is detected. A counter circuit 19 counts up number of idle packets when the information 14 is sent as a result. Count information 23 outputted from the circuit 19 acts like header information designating an outgoing line of a self-routing channel 33. Test pattern information 25 outputted from a test pattern generating circuit 24 is used for an area of channel information of a fixed length packet.</p> |
