| 摘要 |
PURPOSE:To check all ports in a highly efficient and simple way by providing a communication control processing part and a data control part to a device containing plural ports and connecting a terminal equipment to the device to check the outputs of those ports. CONSTITUTION:A communication control processing part 4 of a device 1 containing plural ports writes the data outputted from a data control part 5 via a head port 3-4 of those ports connected in series and at the same time the internal connection is secured to the port 3-4 so that a port 3-3 reads the port 3-4. Then a cable 7 is set outside the device 1 to secure connection among ports. Thus the serial connection is completed among all ports. Under such conditions, an MPU2 actuates the part 5 to write the check data into the port 3-4. The next port 3-3 reads the port 3-4. Such writing and reading actions are repeated and the data written into a port 3-0 is checked by a terminal equipment 6. Thus it is possible to simply check plural ports under the same conditions and to increase the port checking speed. At the same time, the reliability is improved for a port diagnosing system. |
