JPS6053935B2 - Data transmission method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a data transmission method for mutually transmitting data between a controller and a plurality of controlled devices controlled by the controller, and in particular, it is possible to reduce the number of transmission lines, and The object is to provide an interface device and other necessary circuits that can be simplified.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings.

First, an example of a device in the data transmission system of the present invention will be explained with reference to FIG. Reference numeral 1 denotes a single-wire bus line, and a single-core coaxial cable is used, for example.

2a is the controller, 2b to 2e are this controller 2
A is a plurality of controlled devices, three in the illustrated example.

In this case, the controlled equipment is, for example, a television receiver, VTR) or radio receiver. In this example,
In this case, the controlled device 2e is a receiver of control signals, and the control signal from the transmitter 3 is supplied to this receiver 2e, and the data signal (data transmission signal) from this receiver 2e is transmitted to the controller 2a and the controlled device. 2b, 2c, and 2d. The controller 2a and the plurality of controlled devices 2b, 2c, 2d, and 2e are wired or connected to the single bus line 1.
Next, the synchronizing pulse signal supplied from the controller 2a to the single-wire bus line 1 and the data transmission signal supplied to the single-wire bus line 1 from the controller 2a) and the controlled devices 2b to 2e will be described with reference to FIG. 2 and subsequent figures.

A synchronous pulse signal whose waveform is shown in FIG. 2A is constantly sent from the controller 2a to the single-wire bus line 1.
Of course, in this case, the frequency of the synchronizing pulse signal is a desired constant value, and so is the duty factor. From the controller 2a and the controlled devices 2b to 2e, for example, a second
A digital data signal whose waveform is shown in FIG. Ru. Figure 2C
shows the waveform of this data transmission signal. In this example, this data transmission signal is obtained by wire-OR combining a synchronization pulse signal and a digital data signal. In FIG. 2C, this data transmission signal is, for example, "0", "■JO.
It shows that it consists of a serial signal of k "1", "1" and each bit signal. As shown in FIG. 3, this data transmission signal consists of a serial signal of a one-bit start bit signal and a one-word serial word signal consisting of a plurality of data bit signals.

The 1-bit start bit signal is, for example, "1".

The data bit signal is 8 bits in this example. Further, the word signal in this example consists of a 1-bit start bit signal, an 8-bit data bit signal following this, and a 1-bit control bit signal following the 8-bit data bit signal. This control bit signal is shown as C in FIG. 3 for convenience and is either "1" or "0".
”. This will be discussed later. Next, a series of data transmission signals consisting of several word signals sent from the controller 2a or the controlled devices 2b to 2e will be explained with reference to FIG.

First, for example, two words of the device identification number word signal are provided. This is Figure 3. Of the word signals shown in , the data bit signal is provided with a bit signal of "1" or "0" corresponding to the equipment identification number of the above-mentioned controlled equipment. The next data word signal consists of N words, where N depends on the data to be sent.・
In this data word signal, each data bit signal in FIG. 3 is "1" or "0" depending on the data of each one word signal. When the data word signal ends, an end word signal is sent from the controller 2a to the single-wire bus line. As shown in FIG. 5, this end word signal is a signal in which each 8-bit data bit signal is an end bit signal, and in this example, all are "0". When each controlled device detects that eight ROJ end bit signals have been sent after the start bit signal "1" has been sent, it determines that data transmission has ended. After that, if no data transmission signal is sent from the controller 2a and the controlled devices 2b to 2e, this end word signal is repeated and continues to be supplied to the single wire bus line 1. Then, the single wire bus line 1 is connected to the controller 2a and any of the controlled devices 2b to 2e.
If the data transmission signal is to be sent to the single-wire bus line 1, the controller 2a for the next end word signal is sent after sending at least one word of the end word signal to the single wire bus line 1.
Alternatively, the start bit signal of the first word signal of the data transmission signal is synchronized with the specific end bit signal specified according to the plurality of controlled devices 2b to 2e, and thereafter a series of data transmission signals are transmitted over the single-wire bus. It is configured to be sent to line 1.

That is, as shown in FIG.
” for the end bit signals Tl, T2 . . .
...The order is specified as T8, and the controller 2a1 and the controlled device 2b correspond to each other.In this example, the controller 2a and the other seven controlled devices 2b to 2h correspond to timings T1 to T8. are doing. Then, at the corresponding timing of each controller 2a or controlled devices 2b to 2h, the start bit signals of the first word signal of the data transmission signal described above are synchronized, and from then on, each word signal is continuously transmitted in a series. A data transmission signal is transmitted. The start bit signal of the data transmission signal is synchronized by the controller 2a at timing T1, and when simply transmitting an end word signal, the start bit signal is generated at the time of the original start signal "1". , after which the end word signal is sent. Now, in the above-mentioned FIG. 5, it is assumed that data transmission signals can be sent to the single-wire bus line 1 from a total of eight devices, one controller and seven controlled devices.
By periodically changing the control bit signal C to "1" or "0", more controlled devices can be controlled.

That is, as shown in FIG. 6, the control signal of the end word signal is...C=0, C=1, C=1, C=0.
, C=1, C=1, C=0, etc., then when C=1 at the beginning, the data transmission signal from the controller 2a and the controlled devices 2b to 2h is Its priority can be set so that it is supplied to the single-wire bus line, and in the next C=1, the controlled equipment 21 to
The priority is set so that the data transmission signal from 2p is sent to the single-wire bus line, and then when C=0, the data transmission signal from the controlled devices 2q to 2x is supplied to the single-wire bus line. The priority order can be determined. Next, the main parts of the interface device (digital circuit configuration) 5 of the controlled device will be explained with reference to FIG.

This interface device 5 is an interface device for a television receiver that is provided with a channel selection operation button corresponding to each channel and a display device that displays a display according to the channel when the channel selection operation button is pressed. This will be explained using a case as an example. 6 is a switching control circuit for switching channels of the television receiver.

It is assumed that the output of the switching control circuit 6 controls the capacitance control voltage of, for example, a local oscillator of an electronic tuning tuner and a variable capacitance diode of a high frequency tuning circuit. Reference numeral 7 denotes a display device in which a display element comprising a light emitting diode, an incandescent lamp, etc. and displaying the number of channels is provided adjacent to each of the channel selection buttons described above. Reference numeral 9 denotes an operation signal generation circuit that generates a digital channel selection signal in response to operation of a channel selection operation button corresponding to each of the channels described above, which is provided on the front surface of the television receiver.

Reference numeral 10 denotes a switching circuit (multiplexer) for switching the output from the operation signal generating circuit 9, and the output of the switching circuit 10 is switched and supplied to the input sides of the sending register 12 and the self-operating register 13.

This switching circuit 10 is switched and controlled by a control signal from a sending/non-sending changeover switch 11. Reference numeral 8 denotes a receiving circuit connected to the single-wire bus line 1, which is composed of a logic circuit, and is a circuit that sends a data transmission signal to the single-wire bus line 1 and receives a data transmission signal from the single-wire bus line 1. It is.

The output of the transmitting/receiving circuit 8 is supplied to and stored in a register 14 that stores a remote control signal (data transmission signal) from the controller 2a. That is, instead of operating the above-mentioned channel selection operation button to select a television broadcast, the controller 2
When tuning is performed using a remote control (tuning) signal from a, the remote tuning signal is supplied to the register 14 through the transmitting/receiving circuit 8 and stored therein. Then, the output of the register 13 and the output of the register 14 described above are supplied to a switching circuit (multiplexer) 16 and switched. In this switching circuit 16, register 13 and register 1 are controlled by a switching control signal from a self-operated/remote-controlled switch 17
4 outputs can be switched. Further, the output of this switching circuit 16 is supplied together with the output of the register 12 to another switching circuit (multiplexer) 15 for switching. The output of the switching circuit 16 is supplied to the switching circuit 6 described above, and the output of the switching circuit 15 is supplied to the display device 7. Furthermore, the output of this switching circuit 15 is also supplied to the transmitting/receiving circuit 8. Next, the operation of this interface device 5 will be explained.

First, when selecting and operating the channel selection button on the television receiver regardless of the single wire bus line 1 to select a channel, the operation signal generation circuit 9 transfers the channel selection digital signal to the switching circuit 1.
It is switched by 0 and is supplied to the register 13 and stored. The output of this register 13 is the switching circuit 1.
6 and is supplied to the switching control circuit 6 for channel selection. Further, the output of the switching circuit 16 is supplied to the switching circuit 15, and the output of this switching circuit 15 is supplied to the display 7, so that the display element corresponding to the operated channel selection button lights up. Further, when a remote control (tuning) signal from the controller 2a is supplied as a data transmission signal from the single-wire bus line 1 to the transmitting/receiving circuit 8, this remote control (tuning) signal is supplied to the register 14 and stored. and its output is switched by the switching circuit 16 to the switching control circuit 6.
is supplied to the switching circuit 16 for channel selection.
The output is supplied to another switching circuit 15, switched, and supplied to the display 7, and the display element corresponding to that channel is lit in the same manner as described above.

Further, in any of the above-mentioned channel selection states, if, for example, the television broadcast of a certain channel is to be recorded on a TV or VTR between a certain time, a timer is provided in the controller 2a, for example. Then, the time and number of channels for viewing the television broadcast can be supplied as a data transmission signal from the interface device 5 of the television receiver to the controller 2a to make a program reservation.

In this case, the channel to be selected is specified by operating the channel selection operation button, and the switching is controlled by the channel selection signal generated in the operation signal generation circuit 9 and the operation of the transmission/non-transmission changeover switch 11. The signal is switched by the switching circuit 10 and stored in the register 12. The output of this register 12 is then switched by a switching circuit 15 and supplied to the display 7 to display the channel of the television broadcast for which the program is to be reserved. In this case, the channel to be transmitted is displayed either overlappingly with or independently of the channel actually being received. Furthermore, the switching circuit 1
The output of 5 is supplied to a transmitting/receiving circuit 8, whereby a data transmission signal is sent to the single wire bus line 1 and supplied to the controller 2a. In this case, the reception of the television receiver is not affected. Alternatively, you can make this program reservation without directly operating the channel selection operation on the television receiver.
The above-mentioned transmitter 3 supplies the channel designation signal and the five signals indicating the time to receive the broadcast to the receiver 2e, and the program reservation is performed by the data transmission signal sent from the receiver 2e to the single-wire bus line 1. When the data transmission signal is sent from the single wire bus line 1 to the transmitting/receiving circuit 8, it is supplied to the register 14 and recorded! be remembered. The output of this register 14 is switched by a switching circuit 16 and supplied to another switching circuit 15, and then switched and supplied to the transmitting/receiving circuit 8, from which a data transmission signal specifying the channel and listening time is transmitted as described above. controller 2
It will be supplied to a. According to the data transmission method of the present invention described above, the transmission line connecting the controller and the plurality of controlled devices controlled by the same can be one single bus line, and this data transmission signal can be transmitted from the controller. The synchronization pulse signal is pulse-width modulated with a digital data signal, and each data transmission signal is synchronized with the synchronization pulse signal from the controller, and the data transmission signal consists of a start bit signal and multiple data bit signals. Since it is a serial signal of a word signal consisting of a serial signal of Since the settings are preset, data transmission between the controller and multiple controlled devices controlled by it can be performed bidirectionally using a common single-wire bus line. The interface device and other circuit configurations required for the system are extremely simple.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a device used in the method of the present invention, FIG. 2 is a waveform diagram, and FIG. 3 is an explanatory diagram showing a word signal.
Fig. 4 is an explanatory diagram showing data transmission signals, Fig. 5 is an explanatory diagram to explain the end word signal and the transmission order of data transmission signals from the controller and each controlled device, and Fig. 6 is an explanatory diagram showing the number of controlled devices. An explanatory diagram of the control signal in case,
FIG. 7 is a block diagram showing an example of an interface device. 1 is a single wire bus line, 2a is a controller, 2b to 2x
are controlled devices, particularly 2e is a receiver, 3 is a transmitter, and 5 is an interface device.

Claims (1)

[Claims] 1 A controller and a plurality of controlled devices controlled by the controller are wired or connected to a single wire bus line,
The controller constantly sends a synchronous pulse signal to the single-wire bus line, and a data transmission signal obtained by pulse width modulating the synchronous pulse signal with a digital data signal is sent from the controller and the plurality of controlled devices to the single-wire bus line. the data transmission signal is made up of a serial signal of one word serial word signal consisting of a start bit signal and a plurality of data bit signals;
After the controller and any one of the plurality of controlled devices have finished sending a series of data transmission signals to the single wire bus line, the controller transmits the plurality of data bit signals in the word signal. An end word signal each composed of an end bit signal is sent to the single-wire bus line, and a series of data transmission signals is sent from the controller and any one of the plurality of controlled devices to the single-wire bus line. In the case where at least one word of the end word signal is sent to the single wire bus line, the next end word signal is sent to the specific end specified by the controller or each of the plurality of controlled devices. A data transmission system characterized in that a start bit signal of a first word signal of the data transmission signal is synchronized with the bit signal, and thereafter a series of the data transmission signals are sent to the single wire bus line.