JPS62222730A - Data multiplexing transmitter - Google Patents

Abstract

PURPOSE:To improve the transmission efficiency in the transmission through one line and to simplify the transmission/reception circuit by multiplexing with time division a pulse whose amplitude is changed in response to a channel and whose width is changed in response to a data and separating a channel from the amplitude of a pulse train signal and obtaining a data level from the pulse width. CONSTITUTION:A transmission circuit is provided with a pulse width modulation circuit 1 and an amplitude adjusting circuit 2 and extracts a pulse train signal subjected to time division multiplexing in response to the width modulation pulse corresponding to 4 channel data and in response to the amplitude corresponding to the channel as a transmission signal. A reception circuit uses comparators 161-164 using voltages VR1-VR4 corresponding to each channel as comparison references to an input through a transmission line 12 so as to discriminate the amplitude. The output of the comparator 161 among the outputs is extracted by a buffer 176 as it is and the outputs of the comparators 162-164 are extracted by exclusive OR circuits 177-179 respectively as channel separation outputs. Then a demodulation output in response to the pulse width is obtained by meaning circuits 181-184.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for multiplexed pulse transmission of channel data.

B1 Summary of the Invention The present invention is a device that multiplexes data from multiple channels and transmits pulses, in which pulses with varying amplitude #A depending on the channel and width depending on the data are multiplexed and transmitted in a time-division manner. By separating the channels from the part width of the transmitted pulse train signal and obtaining the data level from the pulse width, it is possible to reduce the transmitting and receiving circuits while transmitting over one line and increasing the transmission efficiency. It is strained.

C0 Conventional Technology Conventionally, channel data multiplexing (multiplex transmission) involves time-division multiplexing of data on each channel, and time-division multiplex data communication also includes synchronous and asynchronous methods. be.

In the synchronous type, a bit synchronization signal for temporally identifying data bit divisions is transmitted as a clock on a line different from the data line. In the asynchronous method, synchronization information of start and stop bits is included in the data and transmitted, and the receiving side obtains the timing of the start of a character from the synchronization information and determines the delimitation of bits.

Furthermore, in order to multiplex data of I channels in both synchronous and asynchronous systems, a channel synchronization signal is included in the data, and channels are separated from this synchronization signal.

D0 Problems to be Solved by the Invention According to conventional multiplex transmission, the synchronous type requires two lines for data and clock, while the asynchronous type requires only one line, but the control is complicated due to the asynchronous type. There was a discovery that the effective transmission speed decreased.

In addition, both synchronous and asynchronous multiplexed transmissions require the inclusion of a channel synchronization signal, which requires a circuit for separating and extracting the synchronization signal, resulting in poor transmission efficiency.

1 Means and Function for Solving the Problems The present invention has been made in view of the above-mentioned problems.In an apparatus for multiplexing data of a plurality of channels and transmitting pulses, the present invention provides a method for transmitting width modulated pulses corresponding to each channel data. A transmission circuit that is time-division multiplexed with amplitudes corresponding to channels E, and channels that are separated from the S width of a pulse train signal received from this transmission circuit via a transmission path, and demodulated from the pulse width to a data level. It is equipped with a receiving circuit, distinguishes channels by amplitude, and transmits and receives data in correspondence with each other by pulse width.

F. Example FIG. 1 is a circuit diagram showing an embodiment of the present invention.

The transmission circuit includes a pulse width modulation circuit 1 and an amplitude adjustment circuit 2, and uses, as a transmission signal, a pulse train signal in which width modulation pulses corresponding to four channel data are time-division multiplexed with amplitudes corresponding to the channels. Take it out.

The configuration of the pulse width modulation circuit 1 will be explained. Analog signals from four channels CH1 to OH4 are buffered 3. ~
34, respectively, and are used as comparative forces for each of comparators 41 to 44. The clock generator 5 generates a pulse with a frequency proportional to the transmission speed, and the triangular wave generator 6 generates a triangular wave with a frequency proportional to the output pulse of the clock generator 5. On the other hand, the frequency divider 7 divides the output pulse of the clock generator 5 into 1
/N tC, and a shift pulse (duty 1/4) with the frequency 2 phase of the triangular wave generator 6 matched is obtained in the quaternary link counter 8 which uses the divided output and the shift clock. Analog switch9. ~9. is ring counter 8
The triangular wave generator 6 is turned on sequentially by the shift pulse of
The triangular wave output signals are taken out sequentially and sent to comparators 41 to 4.
4 as the comparison reference signal.

Next, the i#Ax rectifier circuit 2 has voltage dividing resistors 1()1 to 1 that generate voltages at levels corresponding to the four channels f.
06, and the above-mentioned comparator 4.06 is connected between each voltage point and the output terminal. The analog switch 1], which is turned on and off by the output l of ~44, ~11. It is composed of The output pulse of the amplitude g4 adjustment circuit 2 is transmitted to the receiving circuit through the transmission line 12.

The receiving circuit includes an amplitude discrimination circuit 13 and a channel separation/demodulation circuit 14, and separates the channels from the amplitude of the pulse train signal received via the transmission line 12, and demodulates the data level from the separated pulses.

The configuration of the amplitude discrimination circuit 13 will be explained. The impedance of the pulse train signal from the transmission line 12 is changed by the buffer 15,
Comparators [61-16. common comparison input.

Resistance 17. ~17. is each comparator 16. ~16! Provide comparison reference voltages of different levels corresponding to channels.

The channel separation demodulation circuit 14 includes a comparator 16°~
164 output pulses as input, exclusive OR circuits 177 to 17q, and an averaging circuit 1 that generates an analog voltage proportional to the pulse width of these output pulses.
81 to 184, and the outputs of the averaging circuits +8+ to 184 are used to demodulate the four channels.

The operation of such a circuit configuration will be explained with reference to FIGS. 2 and 3.

The waveforms of each part of the transmitting circuit are shown in FIG.

Each voltage of four channels OH1 to OH4 ■1 to v
4, the triangular wave output of the triangular wave generator 6 (Fig. 2 I!
L) is an analog switch 9. ~9. (Fig. 2, c, d, e), and the comparators 41 to 4
41, the levels are compared. Therefore, the outputs of the comparators 41 to 44 (Fig. 2 f, g, h
.

1) Pulses with widths proportional to the channel magnetic pressures V and -V can be obtained. And comparator 4. ~44
Since the output f of the analog switches 111 to 114 are turned on in sequence, the input to the transmission line 12 (Fig. 2 j)
becomes a pulse train signal whose pulse width matches the channel voltages V, to v4 and whose amplitude corresponds to the channel 1.

Next, in the receiving circuit, as shown in the waveform diagram of each part in Fig. 3,
Amplitude discrimination is performed by comparators 161 to 1641, which serve as voltages VR, ~VR, and % comparison standards, corresponding to the input through the transmission line 12 (FIG. 3a), and these comparators 16+S-164 Of each output of comparator 16. The output of is its mother buffer 17
channel separation output (third
Figure b) is taken out and the comparator L/-16°~16
The outputs of 4 are taken out as channel separation outputs (FIG. 3c, a, e) by exclusive OR circuits 17-r to 1711. And averaging circuit 18. ~184, by averaging (for example, integrating) the separated outputs of each channel, the demodulated output according to the pulse width, that is, the channel input voltage ■, ~
Obtain output voltages V, ~v4, respectively proportional to v4.

Note that in the first embodiment, the design of each circuit can be changed as appropriate.

Effects of the Invention As described above, according to the present invention, pulses with different amplitudes depending on the channel and widths depending on the data are multiplexed and transmitted in a time division manner, and these pulses are separated into channels and demodulated. As a result, multiplex transmission f using a single transmission line
This has the effect of improving transmission efficiency and speed by eliminating the need for channel synchronization signals and bit synchronization signals.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing one embodiment of the present invention, and Fig. 2 is a circuit diagram showing an embodiment of the present invention.
FIG. 3 is a time chart of the transmitting side in FIG. 1, and FIG. 3 is a time chart of the receiving side in FIG. 1... Pulse width modulation circuit, 2... Amplitude adjustment circuit, 4I
...Comparator, 8...Ring counter, 12...
Transmission line, ■3... Amplitude discrimination circuit, 14... Channel separation demodulation circuit, [6%... Comparator, 18. ...
Averaging circuit. Figure 2 Sappoku Monk 19 im (χ-t)

Claims (1)

[Claims] A device that multiplexes data from multiple channels and transmits pulses includes a transmission circuit that multiplexes width modulated pulses corresponding to each channel data in a time-division manner with amplitudes corresponding to the channels, and a transmission path from this transmission circuit. 1. A data multiplex transmission device comprising: a receiving circuit that separates channels from the amplitude of a pulse train signal received via the pulse train signal and demodulates the data level from the pulse width.