CN1146782C - Personal computer software transmission system - Google Patents

Abstract

The present invention relates to a system of a soft transmission device which has the calculation functions of all transmission devices which are also called data machines. The calculation functions are realized and executed by a personal computer and a central processing unit (CPU) compatible with the personal computer. By the functions of analog-digital (A/D), digital-analog (D/A) and direct memory access, etc. of a sound blaster, a transmission card, or a transmission device wafer set, etc. which have external data channel arrangement (DAA) interfaces, a user can carry out communication with a remote computer or a remote facsimile apparatus through a network path of a pay station line.

Description

The personal computer software transmission system

The present invention system is about a kind of transmission system, this kind transmission system have as data draw, the function of digital signal processing (DSP) such as communication protocol and data compression, belong to computer realm.

Traditionally, transmitter all or most calculation functions are in the scope of the standard specification of being worked out by overseas call telegram board of consultants (CCITT), for example: V.32bis, v.32, v.22bis, v.22, v.23, v.21, v.17, v.29, v.27ter, v.21channel 2, v.42, v.42bis, MNP1-6, T.30, T.4, Hays AT Command, FAX class 1 and class 2 etc., and, all being nationality is realized by the digital signal processing wafer set of special use, and its actuating code is just deposited in the memory cell of enclosing.

The purpose of this invention is to provide a kind of personal computer software transmission system, the calculation standard that all CCITT are formulated, all can carry out by PC or its compatible computer central processing unit CPU, and its software can deposit in the memory body file of computer, makes transmission system can become a software application of PC.

The solution of the present invention is: the hardware of described transmission interface has one drive circuit, the tone of hanging up in the left channel power output loudspeaker of this circuit, it is the sine tone that when hanging up, produces 3 kilo hertzs of sesames, in regular turn via the interruption of comparer uIA, transistor and relay K 1 with the decision driving circuit, otherwise, when hang up in the end, then driving circuit is connected; One hybrid circuit, when relay K 1 is connected, will be from fax contact JP2 or from speech contact JP1, both one of input signal deliver to transformer T1, mix with audible warning from right channel, deliver to the interior left channel of line; One telephone ring signal circuit when relay K 1 is connected, when speech contact JP1 has signal, makes the speech incoming line and from preface is to connect between the ringdown of the right channel of external computer, the indication transmission system has a speech to squeeze into; One shunt circuit, by most capacitors, the partly shunt of high frequency with fax contact JP2 and speech contact JP1 inputs to hybrid circuit via holding circuit, and other has a holding circuit, protection hybrid circuit and transformer T1; Be stored in the software in the PC, be divided into five programs partly from the upper strata to lower floor, be in regular turn: the form driver, order interface program, agreement and error correcting routine, compression and gunzip and data are drawn program, through carrying out, in the time interval that the direct access storage device DMA of PC interrupts, by from the form driver, call command interface program in regular turn, agreement and error correcting routine, compression and gunzip and data are drawn program, via direct access storage device DMA, transmission in the line, otherwise, import via circuit, draw program partly according to the said sequence reverse call from data, finally arrive the form driver partly, be shown on the terminating machine of PC.

Advantage of the present invention is, owing to do not set up special-purpose digital signal processing wafer set to realize the calculation function of transmitter, make the cost of transmitter reduce many, the advantage that also has software upgrading and re-use simultaneously, another advantage is, can make transmitter become the some of PC, the manufacturer of PC, this transmitter function can be integrated in the computer, the user does not need to do work such as setting, assembling even the fault detect of transmitter or eliminating.

The present invention has following accompanying drawing, and accompanying drawing is made brief description:

Accompanying drawing 1 is action system figure of the present invention.

Accompanying drawing 2 is composition synoptic diagram of the present invention.

Accompanying drawing 3 is that receiver of the present invention partly acts on process flow diagram.

Accompanying drawing 4 is that forwarder of the present invention partly acts on process flow diagram.

Accompanying drawing 5 is planispheres v.22bis.

Accompanying drawing 6 is echo canceller block schemes partly.

Accompanying drawing 7 is hardware circuit embodiment circuit diagrams of the present invention.

Below in conjunction with accompanying drawing principle of the present invention and embodiment are elaborated.

See also accompanying drawing 1, transmitter is a kind of digital signal processing device, it is simulating signal to be transformed to digital signal (A/D) and a digital signal conversion link up mutually with the external world to simulating signal (A/D), along with adlib in the pc domain (audio card) being extensive use of of sound blaster (soundblaster) for example, therefore the present invention's software transmission device system has utilized A/D and the D/A function on adlib or the adlib wafer, more specifically say, this software transmission device utilizes the D/A of sound blaster and the loudspeaker output transmission channel as transmitter, and the line input that utilizes the A/D of sound blaster and another sound channel is as receiving channels; It should be noted that, the tut channel uses 11.025 or 22.05 or 44.01 kilo hertzs sampling frequency to carry out the function of A/D and D/A, and the channel of transmitter is to utilize 7.2 or 8.0 or 9.6 kilo hertzs sampling frequency to decide according to baud rate (baud rate), in order to allow this software transmission device can utilize sound blaster work, needed hardware only is to arrange interface with the direct access that is connected to phone guiding principle road.

The present invention's software transmission device system is in the CPU (central processing unit) of PC, carries out the calculation rule of all transmitters, and nationality is connected to the A/D and the D/A unit of sound blaster or transmission card by the function of direct memory body access (DMA); Delivery unit and receiving element be its function of executed in parallel [full duplex (full duplex)] immediately, in order to reach this purpose, the channel that needs two DMA, and the interruption of DMA is as the inlet point of each delivery unit and receiving element, a buffered frame of sampled data has been collected in the interruption of each DMA channel representative from A/D and D/A element, therefore, this frame rate is the interrupt rate (interrupt rate) according to DMA and deciding, the frame rate of reality of the present invention, for data transmission, be set in 13.3333 milliseconds, and, then be 39.9999 milliseconds the facsimile transmission device; Because the magnetic disc access (disk access) of generation, network frame access potential possibilities such as (network frame access) are arranged, therefore, each delivery unit and receiving element all need a multiple formation frame buffer (queue frame buffers), are called queue buffer; When computer is busy with handling and during other things such as magnetic disc access, the data that are sampled to still can be by this frame buffer of income (for first-in first-out buffer), the integrality that just can guarantee data like this; In the present invention, data link has disposed 64 frame buffers, its transmitter has then disposed 16 impact dampers (data link and facsimile transmission device and execution work not together), all transmitter algorithms are all decided according to frame rate, and each frame buffer all comprises the data that a block is sampled to, for delivery unit, receive the modulation data of data (ASCII or fax pixel) block of processed formation of a block from computer, be copied to the frame buffer of DMA then, after the D/A conversion, output to the loudspeaker output terminal, for receiving element, the data that a block (frame) receives are after the algorithm processing via receiving element, convert computer to and can read and data presented, as shown in Figure 1.

See also Fig. 2, according to the standard of CCITT, this software transmission device can be divided into 5 parts:

1, the form driver partly;

2, order interface part: Hays class 1 and class 2;

3, agreement and error correction part: MNP4, v.42, T30;

4, the compression and part: the MNP5 that decompresses, v.42bis, T4;

5, data are drawn partly: v.32bis, v.32, v.22bis, v.22, v.23, v.21, Bell 212, and Bell 103, and v.29, v.27, v.27ter, v.21 channel 2.

The composition of software transmission device is as shown in Figure 2, all 5 relevant software transmission partly all need the function with instant processing, this represents that promptly they all will be by communication frames (frame, frame, down together) in the defined limited time-frame of speed, finish the work of data processing, data are drawn partly, because it is the work of digital signal processing guiding, need to carry out the computing of many multiplication and integration, so this restriction is even more important, the algorithm that really needs skill is all in this part, therefore we will at length explain this some, and only illustrate simply that other partly.

According to the standard of CCITT, data are drawn, various communication algorithm or scheme are arranged, for example: v.32bis and v.32 be quadrature with echo cancellation and the Trellis error correcting code modulation (QAM) that shakes; V.22bis, be that QMA opens frequency band frequency modulation v.22 with bell 212, v.23, be frequency shift keying (FSK) v.21 with Bell 103; V.17 be half-duplex QAM with Trellis error correcting code; V.29 be half-duplex QAM; V.27ter be differential phase shift keying (DPSK) modulation, v.21 channel 2 is half-duplex FSK modulations.

Because many different communication standards are arranged, we do not plan to illustrate each algorithm or scheme, and on the contrary, we will only describe a typical modulation algorithm.

See also Fig. 3, at receiving element partly, the sampling frequency conversion partly, 11.025 kilo hertzs sampled data of sound channel is transformed into the sampled data (if the sound line input of using sound blaster is as input element) of 7.2 kilo hertzs or 8 kilo hertzs, so that transmitter is handled, through after separating modulation, convert the passband sampled data to the base band sampled data, utilize low pass and pulse shaping filter to reduce intersymbol interference and band external noise simultaneously, above-mentioned wave filter also can be used as the response that matched filter mates channel, signal to one fixing horizontal that receives is partly adjusted in automatic gain control (AGC), power measurement partly then determines to have the state of no signal, signal is cut and is partly reduced the Ni Kui Si frequency of sampling frequency to the baud interval of specific modulation method frequently, sequential interpolation and circulation mark are partly under situation about not worsening because of intersymbol interference, adjust and be phase-locked to the sequential of symbol, partly reduce widely because of the caused intersymbol interference of band limit channel Deng change, it is poor that the carrier wave answer is partly restored by the arteries and veins between the caused carrier wave drift of channel and local and distant place transmitter, signal decision-making mapping partly becomes data bit element with the symbol transition that receives, these data bit elements are then through differential decoding and arrangement, producing at last can be by the data of computer differentiation, the mapping of signal decision-making is a benchmark ideal symbol and deciding, calculate the symbol that receives and the error between fiducial mark then, this error vector can be used for upgrading the coefficient of eqalizing cricuit, we can utilize this eqalizing cricuit that upgraded that the chemical industry such as symbol execution that the next one receives are done, the algorithm that eqalizing cricuit upgrades is laid a foundation in the Minimum Mean Square Error algorithm, and the length of eqalizing cricuit coefficient, because of the difference of standard different.

See also Fig. 4, at forwarder partly, frequency mixer makes the data element randomization to expand the frequency spectrum of last modulation, differential encoder is rearranged the order of coding bit, make that the coding bit that has minimum between adjacent-symbol is poor, the signal map bit of partly will encode is transformed into two-dimentional composition one quadrature component and amplitude, low pass filtered involves shaping pulse and partly is used to and will removes through the high-order harmonic wave that produces behind the modulation, simultaneously also can carry out shaping to sign pulse, make the impulse response of its responses match channel, signal interpolation process from the symbol frequency to the sampling frequency also is encompassed within the above-mentioned filtering scope partly, (to each standard, the frequency response of its channel is all defined by the specification of CCITT), the modulation part is transformed into baseband signal the passband signal of telephone band, sampling frequency conversion partly converts the sampling frequency of 7.2 kilo hertzs of communication channel or 8 kilo hertzs to 11.025 kilo hertzs the sampling frequency (if using sound blaster as output element) of sound channel, after conversion, the signal data of whole block is copied in the frame buffer of DMA, wait for that DMA next time interrupts, other algorithm, such as the agreement layer, the compression layer and the layer that decompresses, order interface layer etc., in the specification of CCITT v.42, v.42bis, T30, among T4 and the Hays AT command, very clearly file specification is all arranged, wherein, v.42 be to come the more X.25 specification of orthofunction of execution error to have HDLC connection framing; V.42bis be to live based on the general data compression mark of writing yard algorithm of Lempel-Ziv; T30 and T4 are the standards of facisimile transmission; T30 has the fax specification that HDLC becomes frame, and T4 lays a foundation to write the data compression standard of yard algorithm in the sweep length Huffman.The Hays AT Command person of being to use orders interface, also is actual standard simultaneously.The form driver in fact is dynamic link library (DLL), is used for replacing form communication driver Comm.drv, order and data that this driver meeting stick-up comes from service routine, and it also can simulate order reaction and the data to application program simultaneously; This driver is to be mounted in the computer simultaneously when software is installed.

See also Fig. 2, it shows the relation of each agreement interlayer, and by and large, control flow is from the PC application program to the communication driver and the order interface, and this order interface is called out the agreement layer, and this agreement layer call data compression layer and data again draws layer; The state of each layer transmits with opposite direction, and red is each layer all reported communication state from itself to its last layer, these states, and wherein a part can arrive the PC application program at last; The advantage of this kind framework layer is to make each standard become a separable module, and this kind isolation makes calling program be easy to safeguard and upgrading that unique requirement is the interface parameter that must define clearly between each layer module (layer) plinth.

Below accompanying drawing is described further:

See also accompanying drawing 4, computer data is randomized, cross through differential code, or encoded through Trellis, and separated homophase channel and the quadrature channel of entering, these channels will be known as I channel and Q channel in the back; Through behind the suitable coding, the data symbol of these I and Q channel can be imported in the low-pass filter, this wave filter and the wave filter of changing as sampling frequency, it can be the wave filter of the formula of traversing, comprise a series of delay-level and sequentially many branches are multiplied by the method for each data symbol dI (j) and dQ (j), each braning factor is all relevant with a certain delay-level, the branch of these wave filters can have fixing coefficient, and these wave filters with receiving element in after similarly wave filter is adjusted together, just can utilize minimized number branch that the performance of system's the best is provided, the product that obtains by these multiplication, added up as the output of this wave filter, these digital signals can be expressed as following two formulas in each other channel:

wI(j)＝∑dI(j+k)※gI(-k)

wQ(j)＝∑dQ(j+k)※gI(-k)

Wherein gI (k) is the branch value of wave digital lowpass filter, a certain specific branch can be designated as gI (o), in the case, continuous branch can be appointed as gI (1) before being positioned at it in this tandem, gI (2) ... gI (k1), just can be appointed as gI (1) and be positioned at continuous thereafter branch, gI (2) ... gI (k2).For in a desirable channel, with Ni Kui Si frequency, per second transmits 2w symbol, and this wave filter can be adjusted to the signal waveform that provides synthetic, and its waveform has following feature:

H (W)=2 Tcos (tw)/2 reaches (w)≤π/T

H (W)=0 is to (w)＞π

T conventional letter cycle wherein.

Under the situation that does not have the channel distortion, this practice will make total system have following impulse response:

h(t)＝4/π [cos(πt/T)/(1-4(t/T)(t/T))]

Can clearly find out when t=± T/2, h (t)=1, and in every other sample time, h (t)=0.

After the suitable filtering of process, signal in I and Q channel can be then by to be multiplied by the mode of the numerical value that from a sine table, takes out, the carrier wave that to carry a last frequency be 1800 hertz (v.32), the signal that these modulations are crossed can then combine in a totalizer, and in a D/A, be transformed into simulating signal, this signal that send in phone line can be expressed as following formula:

s(t)＝wI(j)※cos(wc(t)+wQ(j)※sin(wc(t))

Wherein wI (j) and wQ (j) are the homophase of baseband signal and j data symbol of orthogonal component; And wc is the angular frequency of sin/cos table, we all know, the signal that send in phone line, more or less all can be changed, the degree of its change is the quality of telephone wire and deciding according to this then, these changes are known as signal degradation, for example frequency shift (FS), phase deviation, phase jitter, symmetry or asymmetry postpone, loss distortion, and gaussian sum pulse noise etc. all is, certainly, we expect that receiving element can compensate the tedious characteristic of all these telephone wires, so that the difference between the signal of signal that receives and transmission minimizes, the calcspar of receiving element as shown in Figure 3.

Simulating signal from the telephone wire input, A/D converter with sound blaster or transmission card, convert digital signal to, after this conversion, the signal of all parts of receiving element all is that digital format is via the DMA channel, from the next digital signal of A/D, if make under the situation of sound blaster, then must be with 11.025 kilo hertzs frequency, convert 7.2 kilo hertzs or 8 kilo hertzs to, this is because the sampling frequency of 11.025 (or 22.05) of sound channel kilohertz, and be not suitable for being used for transmitter and handle, the sampling frequency that transmitter is handled must be the integral multiple of baud rate, the conversion of said frequencies is that nationality is carried out by a low-pass filter, after the sampling frequency conversion, digital signal can be multiplied by a carrier wave (being to utilize look-up table simultaneously) respectively, utilize this mode, signal just can be separated to be in harmonious proportion to be separated, and import together in the phase channel and a quadrature channel, in receiving element, this two channel also will be known as I channel and Q channel, the signal of demodulation in I and Q channel, can be through filtering and shaping, become baseband signal, after filtering, the baseband signal of I and Q channel can be handled through cutting frequently, to meet Ni Kui Si frequency, for example: if when using v.22bis transmitter, v.22bis, cause is the transmitter of baud rate 600, its sampling rate of 7200 hertz can be cut and frequently be become 1800 hertz, automatic gain control and power measurement part, it is the critical value that is used for the control signal level and has no signal to exist, after these processing, this two baseband signals XI and XQ in I and Q frequency, be introduced into severally etc. and change in the wave filter, this wave filter respectively has a pair of formula of traversing eqalizing cricuit to I channel and Q channel, and this eqalizing cricuit can be revised the symmetry of telephone wire or the delay and the attenuation distortion of asymmetry, at the output terminal of eqalizing cricuit, signal YI and YQ in I and the Q channel can be expressed as following two formulas;

YI(J)＝∑CI(n)※XI(j-n)-∑CQ(n)※CQ(j-n)

YQ(J)＝∑CI(n)※XQ(j-n)+∑CQ(n)※XI(j-n)

Wherein CI and CQ represent the eqalizing cricuit coefficient in individual channels, and n then is illustrated in the big number of getting of each eqalizing cricuit inner multiplication device; YI and YQ must be multiplied by a phase angle Φ, and to revise its phase place, this phase angle is to be produced by the carrier wave reflex circuit of deciding according to phase angle error Φ at nationality, and these were changed and revised the phase angle mistake, and signal YI ' and QI ' in I and Q channel can be expressed as following two formulas:

YI’(j)＝YI(j)※cosΦ’-YQ(j)※sinΦ’

YQ’(J)＝YQ(j)※cosΦ’+YI(j)※sinΦ’

After gradeization and phase angle correction, signal YI ' and YQ ' with regard to become from the YI of distortion and YQ signal to reparation and signal right, these signals YI ' and YQ ' can be introduced into signal decision-making part, this signal decision-making part is a critical value detector, can with why deciding correct receiving symbol, and be decoded into the coding identical element; This decoding is the approximate symbol that decides the most approaching desirable benchmark symbolic point according to look-up table, and accompanying drawing 5 has been described this decision process.

See also the v.22bis planisphere of accompanying drawing 5, wherein * the fiducial mark point of representative on two-dimentional coordinate, then represent the received signal points on two-dimentional coordinate, above-mentioned decision process is exactly to determine that the signaling point that receives should be near that reference point (RI (J), RQ (j)), j from 1 to 16, therefore, obtain a coding bit with regard to decodable code, simultaneously, also can calculate an error, as follows:

ErrI＝YI’-RI

ErrQ＝YQ’-RQ

This error signal can be used to upgrade eqalizing cricuit and carrier wave recovery function, particularly importantly, if utilize this error signal to do gradeization and phase place correction, then receiving element just can be through revising the defective of compensated input signal, through after having the correction of above-mentioned characteristic, the coding bit that detecting obtains just can be introduced into Trellis demoder, differential demoder and separate in the frequency mixer, and then introduces in the layer that decompresses.

For transmitter v.32 and v.32bis, because delivery unit and receiving element take identical signal spectrum, so need an echo canceller, the pollution of the signal that the signal spectrum that receives is transmitted (echo), so, this echo canceller must be eliminated from near-end and the next echo of far-end hybrid tap, the echo that comes from the near-end hybrid tap is called near-end echo, and the echo that comes from far-end bridge joint trouble just is called the far-end echo, the far-end echo postpones in the call channel conduction to some extent because of signal, be called round-trip delay, and may comprise from the next inhibit signal of satellite, accompanying drawing 6 shows the block scheme of echo cancellers.

About the detailed description of compression/decompression layer and agreement layer, please refer to CCITT v.42, v.42bis, MNP4, MNP5, the file of T30 and T4.

In the echo canceller block scheme in accompanying drawing 6, it is maximum delay that memory body stores, and the delay of lengthening far-end echo canceller, this delay (calculating) with symbol frequency be during the CCITT starting sequence that v.32 and v.32bis specification was limited in calculating and getting, near-end and far-end echo canceller, be actually and traverse formula base band synthesis filter, and its braning factor, then nationality is upgraded by the error signal of calculating gained, for the near-end echo canceller, the update method of its coefficient can be expressed as down two formulas:

CI(j+1)＝CI(j)+k※Re[Err(j)※S ^-1(j-n)]

CQ(J+1)＝CQ(J)+K※Im[Err(j)※S ^-1(j-1)]

Wherein n represents the numbering of branch, j represents sample time,-1 represents conjugation, Re represents the real part of plural numerical value, and Im represents plural numerical value imaginary part, CI and QI are the coefficient of echo canceller, and the baseband demodulation error signal of Err representative behind shortcut and far-end echo canceller is shown below:

Err(j)＝(S(j)-S’(j))※e ^WCT

Wherein S (N) is the signal that A/D receives, s ' is the estimated value of near-end and far-end echo (n), Wc is a carrier frequency, T is-symbol frequency, S is the conventional letter data vector then, the far-end echo is got back to the local reception unit along the call channel propagation, this echo signal of passing back also can be subjected to frequency shift (FS), the influence of phase deviation and phase jitter, phase estimation is designed to estimate the degree of above-mentioned Signal Degrade, and with the defective of compensation telephone wire, phase place output will produce a phase differential Φ, be used for rotation error signal Err, as follows:

Err(j+1)＝Err(j)※Im(e ^WCT)

Be noted that Err is a plural number.

Under the situation of bilateral talk, that is be illustrated in initial training stage upgrade very fast during, update coefficients K will be reduced to a very little numerical value, and when the stage of full duplex communication, renewal rate will reduce.

See also accompanying drawing 7, the framework of hardware of the present invention is by one drive circuit 1, hybrid circuit 2, and telephone ring signal circuit 3, shunt circuit 4 and holding circuit 5 constitute; Wherein the power of left channel output loudspeaker will produce one 3 kilo hertzs sine tone, with pilot relay K1, so that make circuit switching (on hook), line interruption (off hook) also can be for the pulse wave dialing, it is accurate that this circuit can convert above-mentioned sine tone to the high or low position of one direct current (DC), if sine tone produces, the 1st pin of comparer UIA is promptly at noble potential, transistor QI is promptly closed circuit, make electric current flow through relay K 1 coil and interrupt (off hook), if sine tone does not produce, the 1st pin of UIA is promptly at electronegative potential, transistor Q1 promptly opens a way, and stops electric current and flows, and this circuit is promptly under the situation of relaying.

Hybrid circuit 2 is to be used for two channel switch are become the forwarder and the receiver of a channel; Right channel exert oneself be the signal (that is, being converted on the line) that is converted to transformer from forwarder, received signal also will be gone to the left channel in the line of sound programming device (soundblaster) from the transformer line.

3 telephone signals that the ringdown of noble potential can be converted to electronegative potential of telephone ring signal circuit have a phone to squeeze into the indication transmitter.

In shunt circuit 4, capacitor C 5, C6, C9, C10 system are used for radio-frequency signal along separate routes, ferrite (ferrit bead) is to be used for stoping high frequency to be sent on the line, and FB1, FB2, FB3, FB4 do not have high frequency assembly in circuit, for example crystal (crystal) time, can remove from figure.

Holding circuit 5 is to be used for protecting transformer T1 and hybrid circuit 2 not to be subjected to high-voltage electric shock, when a high alternating voltage by relay, it will shorten by this circuit gets back to time on the line.

All conveyor means all need to be integrated into this circuit, just can be connected to the public telephone networking, because this DAA circuit is very simple, so this can be made PC interface card pattern or outside casket pattern, or even small-sized module (similar small-sized matchbox) pattern, if adopt small-sized matchbox module pattern, just it can be directly installed on above the PC host panel, therefore, just can economize next interface slot (with using PC interface card pattern relatively), or a RS-232 serial port (with using outside casket pattern relatively).

If sound blaster is not installed on user's PC, just can use a slice to have A/D, the dedicated transmissions card of D/A and DMA function (this transmission card is the cheap hardware card of a slice), and the transmitter software of transmission card interface therewith can be carried out communication function.

Because the actuating code in the present invention is to be carried out by the CPU (central processing unit) of PC, so, the machine execution time of part CPU (central processing unit) can be shared by this software transmission device, under the environment of DOS, any problem can't take place, and under the Window environment, this software transmission device will reduce the execution speed of other application programs, but, behind DTD, these application programs will be returned to original execution speed, so the user can't feel the reduction on this execution speed.

Claims (3)

1, a kind of personal computer software transmission system, comprise the hardware of fax and speech transmissions interface, be stored in the software in the PC, it is characterized in that: the hardware of described transmission interface has one drive circuit, the tone of hanging up in the left channel power output loudspeaker of this circuit, be the sine tone that when hanging up, produces 3 kilo hertzs of sesames, in regular turn via the interruption of comparer (uIA), transistor and relay (K1) with the decision driving circuit, otherwise, when hang up in the end, then driving circuit is connected; One hybrid circuit, when relay (K1) is connected, will be from fax contact (JP2) or from speech contact (JP1), both one of input signal deliver to transformer (T1), mix with audible warning from right channel, deliver to the interior left channel of line; One telephone ring signal circuit; when relay (K1) is connected; when speech contact (JP1) when signal is arranged, make between speech incoming line and the ringdown to be connected from the right channel of external computer, the indication transmission system has a speech to squeeze into; one shunt circuit; by most capacitors, the high frequency of will fax contact (JP2) and speech contact (JP1) partly along separate routes, inputs to hybrid circuit via holding circuit; other has a holding circuit, protection hybrid circuit and transformer (T1).

2, by the described personal computer software transmission system of claim 1, it is characterized in that: be stored in the software in the PC, be divided into five programs partly from the upper strata to lower floor, be in regular turn: the form driver, order interface program, agreement and error correcting routine, compression and gunzip and data are drawn program, through carrying out, in the time interval that the direct access storage device (DMA) of PC interrupts, by from the form driver, call command interface program in regular turn, agreement and error correcting routine, compression and gunzip and data are drawn program, via direct access storage device (DMA), transmission in the line, otherwise, import via circuit, draw program partly according to the said sequence reverse call from data, finally arrive the form driver partly, be shown on the terminating machine of PC.

3, by the described personal computer software transmission system of claim 1, it is characterized in that: be stored in the software in the PC, be divided into five programs partly from the upper strata to lower floor, be in regular turn: the form driver, order interface program, agreement and error correcting routine, compression and gunzip and data are drawn program, through carrying out, by from the form driver, call command interface program in regular turn, agreement and error correcting routine, compression and gunzip and data are drawn program, via direct access storage device (DMA), transmission in the line, otherwise,, draw program partly according to the said sequence reverse call from data via the circuit input, the final form driver part that arrives is shown on the terminating machine of PC.

Images