Arrangement for interfacing a telephone device with a personal computer

DETAILED DESCRIPTION Referring now to FIG.
1 of the drawing, there is shown a telephone device 300 which incorporates an arrangement for interfacing such telephone device with a personal computer 110.
The telephone device 300 connects to the personal computer 110 over a cable through an RS-232 interface.
The telephone device is also connected to the public switched telephone network over at least one analog telephone line which terminates in an RJ11 jack.
Also optionally included in the housing that contains the telephone device 300 is a 1330 digital answering system.
Such an answering system is presently available from AT&T.
FIG.
2 shows a drawing of the top surface of the housing for the telephone device 300 shown in FIG.
1 for illustrating various features and functions that are available at this device.
Referring next to FIG.
3, there is shown a high-level block diagram of a two line telephone device with a computer interface, in accordance with the disclosed invention.
This combination or system interfaces with a central office over tip-ring line pairs 101, 102 and 103, 104.
Although functionally equivalent with the same circuitry, tip-ring line pair 103, 104 and its circuitry are not shown in the same detail as tip-ring line pair 102, 103.
Thus the explanation herein will make reference to the tip-ring line pair 102, 103.
Connected to tip-ring line pair 101 and 102 are a ringer detect circuit 111 and a Caller-ID decoder and sniff circuit 112.
This circuit not only provides information as to the identity of an incoming call provided through the caller-ID function, but also provides information as to the on or off hook status of other telephone sets also connected to the tip-ring lines 101 and 102.
The caller-ID portion of circuit 112 is also employed as a demodulator for demodulating incoming data signals up to and including 1200 bits/second.
This sniff circuitry portion of circuit 112 detects the busy status of a called telephone number by determining the cadence of the busy tone provided over the tip-ring lines 101 and 102