| 摘要 |
PURPOSE:To understand the transfer status of data in a data bus easily by generating an error signal immediately when a fault such as breaking and short is generated and signals can not be generated precisely. CONSTITUTION:When write data is fed to one input terminal of an EOR circuit 30, the circuit 30 compares the previous inputted write data with the transferred write data; if both write data consist with each other, ''0'' is outputted and, when no consistence is detected, ''1'' is held in FF31. At the time of reading, a read data signal is outputted from an AND circuit 20, sent to an AND circuit 11 through the bus 4 and supplied to the circuit 30. The same signal is inputted to the other input terminal of the circuit 30 through a bus 3. The circuit 30 and FF31 operate in the same manner as the write operation and, when an error is generated, an error signal is generated. |
