JPS6275545U

JPS6275545U -

Info

Publication number: JPS6275545U
Application number: JP16668085U
Authority: JP
Priority date: 1985-10-31
Filing date: 1985-10-31
Publication date: 1987-05-14

Description

[Brief explanation of the drawing]

第１図は本考案の一実施例のブロツク図、第２
図は従来の上位装置と下位装置との接続を示す回
路図、第３図は従来の下位装置のインタフエース
回路の一構成例のブロツク図、第４図は従来の下
位装置のインタフエース回路の他の構成例のブロ
ツク図、第５図は第１図の構成の具体的な回路図
、及び第６図は第１図の構成の他の具体的な回路
図である。１１……接続部、１２……ドライバ／レシーバ
、１３……検出部、１４……切替部、Ｒ１，Ｒ２
……レシーバ、Ｄ１，Ｄ２……ドライバ、ＲＬ１
……リレー巻線、ｒｉ１……リレー接点、ＣＰ１
……コンパレータ、Ｔｒ１……トランジスタ。 Fig. 1 is a block diagram of an embodiment of the present invention;
The figure is a circuit diagram showing the connection between a conventional higher-level device and a lower-level device, FIG. 3 is a block diagram of an example of a configuration of an interface circuit of a conventional lower-level device, and FIG. 4 is a circuit diagram of a conventional interface circuit of a lower-level device. FIG. 5 is a block diagram of another configuration example, and FIG. 5 is a specific circuit diagram of the configuration of FIG. 1, and FIG. 6 is a specific circuit diagram of another configuration of FIG. 11... Connection section, 12... Driver/receiver, 13... Detection section, 14... Switching section, R1, R2
...Receiver, D1, D2 ...Driver, RL1
...Relay winding, ri1...Relay contact, CP1
...Comparator, Tr1...Transistor.

Claims

[Claims for Utility Model Registration] In an interface circuit of a lower-level device that can be connected to a higher-level device, a detection unit that determines whether or not the upper-level device is connected; An interface circuit comprising: a switching section that switches between an external power supply supplied from a higher-level device and an internal power supply of a lower-level device depending on the result.