| 摘要 |
PURPOSE:To increase the availability of a system, by setting a bit value corresponding to each channel based on the result of initial diagnosis to a connection register provided to a channel controller controlling the data transfer with an input and output device. CONSTITUTION:When an initial set signal is inputted to a data transfer device 1 from a diagnosis processor 5, all logical circuits in a channel controller 11 and channels 121-124 are initially set. At the same time, a diagnostic program is stored in a microprogram memory 13 from the processor 5. This program sets the value of a connection register 18 in the state of all channel connection. Next, one channel is selected at a channel interface selection and distribution circuit 16, a microprogram controlling circuit 14 and a transfer controlling circuit 15 are operated for the transfer operation diagnosis of this channel. If a failure is found, a bit to a failed channel of the register 18 is reset to a cut- off state and the next channel is selected for diagnosis. Thus, a failure of the device 11 due to channel failures can be avoided. |
