JPH0191390U - - Google Patents

Description

[Brief explanation of the drawing]

Figures 1 to 3 are diagrams showing one embodiment of the present invention, in which Figure 1 is a block diagram showing the circuit configuration, and Figures 2 and 3 are flow charts showing call control processing by a microcomputer. be. DESCRIPTION OF SYMBOLS 1... Electronic switchboard, 3 ₁ , 3 ₂ ... Outside line interface, 4 ₁ to 4 _n ... Extension telephone, 5 ₁ to 5 _n ... Extension interface, 6... Cross point switch, 7... Tone generation circuit, 8... Hold circuit, 10...Bell sound generation circuit, 11...Microcomputer.

Claims (1)

[Scope of utility model registration request] An outside line interface connected to the line, multiple extension interfaces each connected to a standard extension telephone, a crosspoint switch connecting each of these interfaces, a hold circuit that controls the hold of the outside line and extension line during a call, and a ringtone. In an alternating communication device equipped with an electronic exchange equipped with a generating circuit,
The electronic exchange controls the crosspoint switch and the hold circuit in response to a hold signal from the first extension telephone during a call to put the telephone in progress on hold, and also controls the dial signal from the first extension telephone. a first telephone call means that sends a bell signal from a bell sound generation circuit to a corresponding second extension telephone and controls the cross point switch by off-hook of the second extension telephone to put the telephone in a telephone conversation state; controlling the crosspoint switch and the hold circuit by means of a hold signal from the first extension telephone during a call to put the second extension telephone on hold; 2. An alternate call device comprising: a second call means that controls the cross point switch according to an alternate call signal to place the telephone set on hold last time into a call state.