| 摘要 |
PURPOSE:To attain the transmission with the same program without changing a request program of program control even is a transmitter is changed over, by converting addresses with an interface. CONSTITUTION:If a failure takes place in an M-ST(normal transmitter) 18 and no transmission happens, the M-ST18 amkes a failure signal 22 active. When the failure signal 22 is made active, a B-ST (backup transmitter) 21 accesses a PC (programmable controller) memory and makes transmission/reception with other stations in place of the M-ST18. An interface 12 adds X[2,000] to a requested system address and converts the address into the system address of the B-ST21 when accessing is done from a PC8 to the data area and control area of the M-ST18 on a system bus 15 while the failure signal is active, and accesses the data area and control area of the B-ST21. |
