| 摘要 |
PURPOSE:To attain simple check by storing a data to a register simultaneously at the memory write to a random access memory, reading it from the memory and inputting it to a read register so as to compare both the registers. CONSTITUTION:By which switching pattern a data is to be transmitted is decided by using line switch control information and the switching pattern data is outputted from a switch pattern decision section 1 to a switch circuit 2 and an information storage circuit 3. When a data (1) is inputted, a RAM5 writes it by using a selector section 7. The address of the selected in this case is designated by address information (2). The data is stored in a register 9 at the same time as the write to the RAM5, the data written in the next RAM is read to a buffer register 8, the data in the registers 8, 9 is compared by a comparator 10 and when they are identical, no error information (4) is outputted so as to guarantee the reliability of line route information (3) displayed at present. |
