| 摘要 |
PURPOSE:To enable to switch the input/output device without changing the device address transmitted from the central processing unit from the software, by setting the act display corresponding to the input/output device to be switched. CONSTITUTION:When starting is made from a central processing unit CC1, a device address is transmitted to an input and output bus 2. Since the same address is assigned to the input/output devices I/O #0-3 and #1-4, a coincidence signal is output from matching circuits MAT8, 9. On the other hand, in a monitor section SUP5, the output of an act display circuit 10 indicating the use of any of I/O sets either I/O #0-3 or #1-4. Accordingly, either one gate is open for AND gates 12, 13 determining the starting of main control sections 11 and 12. That is, the device address is transmitted to start either one of I/O #0-3 or #1-4 from CC1, and one of them is selected at the acting display circuit 10. |
