PURPOSE: To simplify the constitution of a device and to improve the data transfer efficiency, by providing respectively an interruption signal transmitting and detecting circuit to a bus controller which transfers data and a terminal device, and transmitting an interruption signal via the middle point of winding of a coupling transformer.
CONSTITUTION: The bus controller 11 and plural terminal devices 22-1∼22-N are connected via bus lines 30A, 30B, and the controller 11 is provided with a bus control protocol controller 12, transmission/receiving circuits 111A, 111B and an interruption signal detecting circuit 113. Further, the devices 22-1∼22-N are provided with a terminal control protocol controller 222, transmission and receiving circuits 111A', 111B' and the interruption signal transmission circuit 221. Moreover, the circuits 113, 221 are connected to the coupling transformers T3, T3' provided to the devices 11 and 22-1∼22-N, an interruption signal is transmitted mutually via the middle point of the winding of the coupling transformers T1, T2 and T1', T2' to simplify the constitution of a multiplex data bus terminal device, allowing to improve the data transfer efficiency.
TAKIMOTO YOSHIO
MATSUZAWA HIDEAKI
NIPPON ELECTRIC CO
| JPS55156449A | 1980-12-05 | |||
| JPS554752A | 1980-01-14 |