PURPOSE: To control contention easily at random by assigning information transmission request timing to every device, and allowing a master device which discriminates the request to send out a permit signal and permit the transmission of information.
CONSTITUTION: For example, a device A1 sends out a request signal R1 and a device A3 sends out a request signal R3. Then, a master device MU sends out a permit signal P1 to a permit line B at the timing corresponding to the device A1 unless information transmission is in process when the request signal R1 is received and detected. The device A1 receives this permit signal P1 to send out information D1. the device A3 keeps on sending the request signal R3 at its assigned timing until a permit signal P3 to the request signal R3 is received, and sends out information D3 on receiving the permit signal P3.
| JPS58192122 | TERMINAL CONTROLLING DEVICE |
| JPS60181958 | DATA PROCESSING SYSTEM |
NARA TAKASHI
KAWATO YUTAKA
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