CN2186976Y - Portable general telephone fee counter - Google Patents

Abstract

The utility model relates to a portable telephone fee counter, which is composed of a single chip computer, a button circuit, an EPROM, an E< 2 >PROM, a power supply control circuit, a decoding display circuit, a telephone interface circuit which has reversal detection, and a ring back tone detection circuit. A forced timing circuit, a reversal detection circuit, and the ring back tone detection circuit are parallel accessed into the single chip computer, and the priority order is determined according to the sequence. The telephone fee counter adopts three control timing circuits which parallel exert actions on the single chip computer, and the accuracy and the reliability of the fee and time count can be guaranteed. The utility model is suitable for various telephone circuit pulses, and the dual tone multiple frequency compatibility, and has the advantages of low power consumption, and convenient operation.

Description

Portable general telephone fee counter

The utility model relates to the message accounting that in the telephonic communication calling party is used circuit.

China has developed multiple Telephone Time-Count, counting equipment at present, these counting equipments, and can be divided into three kinds according to detection method: the anti-polar signal that 1. utilizes switch to provide starts the message accounting of timing.As CN2051422, CN2068738, CN2106457, CN1039691 etc.2. utilize the message accounting of ring-back tone as foundation, as CN2052996, CN2045559 etc.3. the counting equipment of start-up by hand timing circuit, as CN2087407, CN2110322 etc.Because ordinary telephone wiring can not provide anti-polar signal, so the 1. type the counting equipment is limited to the direct distance dialing circuit, but it has advantage accurately, when especially making a long-distance call.The 2. type the counting equipment is applicable to plain old telephone, but in use, ring-back tone often occurs unusual, thereby causes mistake meter and wrong meter to wait the inaccurate phenomenon of chargeing, and therefore the accuracy and the reliability of chargeing is lower.3. type for, then do not belong to automatic charging, can be when not having anti-polar signal or ring-back tone unusual by the accurate timing of artificial assurance.

The purpose of this utility model is a kind of novel portable general telephone charge counter of design, this taximeter adopts low-power scm as microprocessor, be provided with circuit, and be aided with " strong meter " key, thereby guarantee the accurate and reliable of charging the detection and the processing of ringing tone signal and anti-polar signal.

The utility model telephone charge counter comprises low-power scm 1 and the power control circuit 2, EPROM3, the E that are connected with single-chip microcomputer ²PROM4, key circuit 5, telephone interface circuit 6, DTMF decoder 7, decoding display circuit 9.It is characterized in that being provided with the ring-back tone testing circuit 8 that is connected with single-chip microcomputer 1 and seals in phone A line or B line, it comprises:

A, a coupler are coupled to ringing tone signal the input of input protection circuit;

B, an input protection circuit below 0.7V, and are exported to zero-crossing comparator with the amplitude limitation of input signal;

C, a zero-crossing comparator are normalized to the identical unipolar pulse signal of amplitude with the voltage input signal of different amplitudes, and export to lock to loop circuit;

D, a lock, to effective low level output of unipolar pulse input signal generation of a certain fixed frequency band and are sent this output signal into single-chip microcomputer and are handled to loop circuit.

Another feature of the present utility model is, above-mentioned ring-back tone testing circuit 8, contain the telephone interface circuit 6 of antipole measuring ability and contain the key circuit 5 parallel single-chip microcomputers that insert that force clocking capability, and by forcing timing, the order that antipole detects, ring-back tone detects is determined priority.

The utility model telephone charge counter.Adopted advanced instrumentation means, can carry out instrumentation the air time of various telephone lines, and according to the conversation regional computational costs, paired pulses, the dual-tone multifrequency phone is all applicable, Fare determined by travel time accurately and reliably, power consumption is extremely low, and is easy to use.

Fig. 1 is the utility model system block diagram.

Fig. 2 is the electrical schematic diagram of the utility model echo testing circuit.

Fig. 3 is the utility model E ²The PROM connection diagram.

Fig. 4 is the utility model pulse burr handling procedure block diagram

Fig. 5 is the utility model anti-polar signal, ring-back tone detection signal and start-up by hand signal three's a process chart.

Embodiment:

Referring to figure one.Square frame 1 is a central microprocessor, adopt Philips to produce low consumption single-chip microcomputer 80CL31, this kind single-chip microcomputer can be worked under the low operating frequency of low supply voltage, the clock work frequency is 200KHZ in this circuit, because read-write frequency is low, so the power consumption of peripheral circuit is also low, and the work clock of the MCS51 series monolithic of Intel series must not be lower than 1.2MHZ.

Square frame 2 is a power control circuit.It can finish the control to circuit power, when pressing "start" button, the direct-current power supply operating circuit that external power source can be provided; When circuit is in idle state for a long time, when needing energy-conservation outage, the control signal of being sent by single-chip microcomputer can make external power source and internal circuit cut-out.Power control circuit itself is in the normal open electricity condition, and its power consumption is extremely low.

Square frame 3 is EPROM, wherein has run time version and prefix table.

Square frame 4 is for depositing the erasable read-only memory that removes of Fee Schedule, and numerical value wherein can be revised by telephone key-press.

Square frame 5 is a key circuit." startup ", " wheel is looked into ", " strong meter " three function buttons have been adopted in the utility model." startup " button enters normal operating conditions in order to the circuit that " waking up " has been in the reducing power consumption state; Press " wheel is looked into " key, can distinguish enquiry number, the duration of call and expense; " strong meter " key then when no anti-polar signal and ring-back tone are unusual implementation force timing.

Square frame 6 comprises plucking/the on-hook detection that for detecting the telephone interface circuit of telephone state antipole detects.In the long distance lines of anti-polar signal were provided, in case callee's off-hook, switch then can provide anti-polar signal, and single-chip microcomputer then picks up counting in view of the above.When using pulse telephone, whenever by a number, telephone line then shows as continuous break-make, plucks/hang then output pulse string of detection port, and single-chip microcomputer can obtain number value after it is handled.

Square frame 7 is the DTMF decoding circuit, and the dtmf signal that the DTMF phone can be sent is decoded into phone number value.

Square frame 8 is the ring-back tone testing circuit, and the call signal of the frequency of occurrences in 400～500HZ scope whether in its monitoring telephone circuit as busy tone, ring-back, handled for single-chip microcomputer if any then exporting significant level.

Square frame 9 is for showing the LCD liquid crystal display circuit of various information, and the utility model adopts 6 character LCD, and its highest order (first) is as the condition prompting position, as " H " expression number; " P " represents price; " one " express time etc.

With reference to figure two, V1, V2 are used for detecting dislodging state, pulse number and anti-polar signal.S1, S2 are held A line or the B line that seals in telephone wire, when electric current in the circuit is shown in figure two, U1 reflection dislodging state, when using the pulse telephone dialing, U1 is output as pulse train, can obtain corresponding pulse number to its processing; U2 is used for detecting anti-polar signal, in order to start timing.Actual installation does not limit polarity, and as for that detects pulse among U1, the U2, which detects the anti-polar signal single-chip microcomputer and can judge.

Instrument transformer T among Fig. 2 is an audio frequency transformer, and when in the circuit bell signal being arranged, the secondary induction signal of audio frequency transformer is enough to defective chip, D1, and the protective circuit that D2 forms can be limited in signal amplitude below the 0.7V.

Because the ring-back tone power of phone alters a great deal, the input range that has surpassed the testing circuit requirement, for with signal normalization, adopted comparison circuit, the signal that amplitude is varied in size through zero-crossing comparator U3 after, become the bipolar pulse signal that amplitude is equal to, this pulse is through diode D3 and R3, become the unipolar pulse signal behind the R4, again through R3, form the input signal that U5 allows after the R4 dividing potential drop, U5 is a phase-locked loop circuit, when frequency input signal falls into the frequency band of circuit capacitance resistance ware decision, then produce effective low level at output, detect 450HZ in the utility model, the backward signalling that continues second in case ring-back tone occurs, then produces effective low level at output.

Figure three is E ²PROM chip and single-chip microcomputer connection diagram.E ²PROM is the electric erasable read-only memory, and it is used for depositing long-distance rate.For reducing cost, reduce circuit power consumption, reducing volume, the utility model adopts the CMOS Serial E ²PROM.This chip internal is furnished with and boosts and timing circuit, and circuit only need provide+the 5V power supply, by CPU send instruction, data can be revised the numerical value in the internal element.Overcome the disadvantage that present counting equipment rate is difficult for modification.Telephone rate among CNZO51422, the CN1039691 is fixed, and revises as desire, must adopt the EPROM write device, finishes the modification of rate outside message accounting separately; Although CN2106457 provides EPROM write circuit, but still need former EPROM is transferred to, inserting new EPROM can.When this device is revised rate in desire, need only press number " 000 ", import trunk code (or tabulation sequence number) then and import rate again and promptly finish modification rate.

Figure four is processing block diagrams of pulse burr.Because telephone line signal complexity, burr often appears in pulse signal, has influenced the accuracy that number obtains.Adopted shaping among the CN2051422, integration, hardware circuit such as monostable are removed stingless, the utility model is from reducing power consumption, reduce volume, adopting software to eliminate the influence of burr, its basic thought CPU regularly samples to the photoelectric tube output signal, carry out statistical disposition then, its processing procedure is shown in figure four.Because the phone pulse ratio is (so pulse duration＞10ms) can think burr for short burst pulse of duration slowly.C1 is the narrowest negative pulse width (width is by the reflection of sampled point number) among the figure four, and C2 is the narrowest positive pulse width, and PO is " 0 " state initial count value, and P1 is the one state initial count value.

Figure five has reflected anti-polar signal, the relation between ring-back tone detection signal and the start-up by hand signal three.After telephone number has been dialled, just occupied as callee's circuit, switch then provides 0.5 second busy tone (0.5 second duration) at interval, as callee's line idle, then switch is sent 450HZ to the calling party, the ring-back tone of 1 second duration, so if the 450HZ signal do not occur, calling party and callee can not connect, so at first detect the 450HZ signal in the program, promptly start timer (4 seconds) after the appearance, detect " craft " then and start tag unit (by interrupting setting), start sign effectively as " craft ", then enter time status; As the invalid antipole sign that then detects, occur as antipole, then enter time status; The two is all invalid as above, can pick up counting, and as ring-back tone occurred in 4 seconds, not off-hook of callee is described then, and the 4 seconds timers of must resetting repeat said process; Disappear as ring-back tone, show callee's off-hook, pick up counting, as detect busy tone, then skip to reset mode, reenter number and obtain program.

Claims (2)

1, portable general telephone charge counter comprises low-power scm [1] and the power control circuit [2], the EPROM[3 that are connected with this single-chip microcomputer [1]], E ²PROM[4], key circuit [5], telephone interface circuit [6], DTMF decoder [7], LCD decipher display circuit [9].It is characterized in that being provided with the ring-back tone testing circuit [8] that is connected with single-chip microcomputer [1] and seals in phone A line or B line, it comprises:

A, a coupler are coupled to ringing tone signal the input of input protection circuit;

B, an input protection circuit are limited in the spoke value of input signal below 0.7 volt, and export to zero-crossing comparator;

C, a zero-crossing comparator are normalized to the identical unipolar pulse signal of amplitude with the voltage signal of different amplitudes of input, and export to phase-locked loop circuit;

D, a phase-locked loop circuit are exported effective low level of unipolar pulse input signal generation of a certain fixed frequency band, and this output signal are sent into single-chip microcomputer.

2, telephone charge counter according to claim 1, it is characterized in that described ring-back tone testing circuit ［ 8 ］, contain the telephony interface ［ 6 ］ of antipole testing circuit and contain the parallel single-chip microcomputer ［ 1 ］ that inserts of the key circuit ［ 5 ］ that forces timing circuit, and timing, antipole detect, the order of ring-back tone detection is determined priority by forcing.

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