JPH0482445A - Communication equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a communication device capable of communicating data by interconnecting an unlimited number of stations using a single-line data bus wire.

Conventional technology Traditionally, as a communication method between multiple stations, data communication using 2-wire lines, 3-wire lines, or when using 1-wire line, the system clock of the transmitting station and receiving station A synchronized method has been used.

First, an example of a conventional communication system using two wires will be described. FIG. 3 is a block diagram of a conventional communication system using two wire lines. 1 is the transmitting station, 3.4 is the receiving station, 5
is a data bus wire connecting them, and 6 is a clock wire. Further, FIG. 5 is a waveform diagram of the data bus wire 5 and the clock wire 6 during communication, where b is the waveform of the data bus wire 5 and C is the waveform of the clock wire 6.

The operation of the communication system using the two-wire line as described above will be explained below. In the configuration shown in Fig. 3, first, when transmitting 11011010 from the transmitting station 1, a waveform C is sent to the data wire 5 and a waveform C is sent to the clock wire 6 so that one clock is output for each data. Output. Receiving stations 3 and 4 input this, and when waveform C falls, they take in the waveform and determine whether the waveform is H level or L level, and if it is H level, it is "1", and if it is L level, it is "0". Communication can be performed by receiving and receiving data.

Next, an example of a conventional communication method using a single line will be described. FIG. 4 is a block diagram of a conventional communication system using one line. As in the case of a two-wire line, 1 is a transmitting station, 3.4 is a receiving station, 5 is a data bus wire connecting them, and 7 is a system clock wire.

The operation of the communication method using one line as described above will be explained below. In the configuration shown in FIG. 4, when sending 11011010 from the transmitting station 1, it outputs a waveform to the data bus wire 5 as in the case of a two-wire line, and the receiving stations 3 and 4 input this waveform. do. At this time, by making the system clocks of transmitting station 1 and receiving stations 3 and 4 common as shown in FIG.
The waveform a sent from the data bus wire 5 is synchronized, and it is determined whether the waveform a is an H level or an LL level.
Communication can be performed by receiving and receiving data of "1" if the level is "0" and if the data is "0" if the level is L.

However, the conventional one-line system described above has the problem that it cannot be used between stations with different system clocks because it is necessary to synchronize the transmitting station and the receiving station. In addition, it is difficult to indicate the start and end of transmission even between stations with the same system clock, making it impossible to use multiple transmitting stations. Two lines were needed.

The present invention solves the above-mentioned conventional problems. Even in a single line, the system clocks of the transmitting station and receiving station can be used between stations with different system clocks. Furthermore, by being able to indicate the start and end of transmission, multiple clocks can be used. It is an object of the present invention to provide a communication method that can use a number of transmitting stations and also allows reliable communication without data errors.

In order to achieve an object that is more than a means for solving the problem, the present invention connects a plurality of stations with a single line, and transmits a data focus sequence between at least one transmitting station and at least one receiving station. A data wire is provided for transmission, and the data wire is a data bus wire, and a long pulse signal longer than an arbitrary multiple of the reference pulse signal length and the reference pulse signal are connected to the data bus wire, following the reference pulse signal. This is a communication method that sends a data bit sequence consisting of a short pulse signal shorter than an arbitrary times the length of the data bit sequence.It is also a communication method that sends a transmission start signal and a transmission end signal before and after the data bit sequence, and furthermore, the pulse interval is This is a communication device in which the length of the pulse is set to be different from the length of any pulse.

Function: This method allows one-line communication even between transmitting and receiving stations with different system clocks, and also allows the use of multiple transmitting stations by indicating the start and end of transmission. Furthermore, it is possible to perform communication without communication errors.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a communication device (system) in one embodiment of the present invention. In FIG. 1, 1 and 2 are transmitting stations, 3.4 is a receiving station, and 5 is a data bus wire connecting the transmitting station 1.2 and the receiving stations 3 and 4.

FIG. 2 is a waveform diagram of the data bus wire 5 during communication according to an embodiment of the present invention. In FIG. 2, a is a waveform during communication on the data bus wire 5, A is a reference pulse signal, and B is a long pulse signal that is at least m times longer in pulse width than the pulse width of the reference pulse signal A. , C are short pulse signals having a pulse width shorter than n times the pulse width of the reference pulse signal A. The H level at the break of the pulse signal has a width shorter than three times the pulse width of the reference pulse signal A. However, jl
m and n are positive numbers, m)n.

The operation of the communication method of this embodiment in the system configured as described above will be explained below.

In this embodiment, the data bus wire 5 is
is set at H level, and the data to be communicated is outputted at L level. When transmitting 11011010 from transmitting station 1, first, transmitting station 1 outputs reference pulse signal A having an arbitrary pulse width as shown in waveform a. Next, in order to transmit 11011010, transmitting station 1 sends a long pulse signal B as shown in waveform a.
, long pulse signal B, short pulse signal C1 long pulse signal B long pulse signal 13, short pulse signal C, long pulse signal B
, short pulse signal C in order, and the receiving stations 3 and 4 set the pulse signal whose pulse width is longer than twice the pulse width of the reference pulse signal A received first as "1", and output the pulse signal as "1". A pulse signal shorter than twice the pulse width of pulse signal A is received as "0". Here, k is a positive number such that m>k>n.

As described above, according to the present embodiment, the system clock is generated by representing the data bit (.) sequence by the magnitude relationship between the pulse width twice the pulse width of the reference pulse signal A and the pulse width of the pulse signal representing the take bit. It is possible to communicate over a single line even between stations with different values, and if the pulse width of the long pulse signal B representing the take bit sequence output from the transmitting station 1 is longer than m times the pulse width of the reference pulse signal A, Pulse signal C
The pulse width of the reference pulse signal A is set to be shorter than n times the pulse width of the reference pulse signal A, and the receiving stations 3 and 4 set the pulse signal having a pulse width longer than twice the pulse width of the reference pulse signal A to "1", and A pulse signal shorter than twice the pulse width of signal A “
By receiving the data as 0°° and setting a difference in k, m, and n by setting m>k>n, it is possible to reliably communicate without data errors.

Furthermore, if the reference pulse signal A sent before the data bit sequence is set as the transmission start signal, the transmitting station 2 can stop transmitting when the reference pulse signal A is transmitted from the transmitting station 1, and The receiving station 3.4 waits for reception. On the other hand, in this embodiment, as shown in FIG.
After the soto series, that is, after the last short pulse signal C, there is a no-pulse state (H level) that is longer than three times the pulse signal length (reference), or if such a state is defined as the transmission end signal. By this non-pulse state, the transmitting station 2 knows that the transmission from the transmitting station 1 has ended, and is allowed to transmit.

In this way, by sending a transmission start signal and a transmission end signal before and after a data bit sequence, it is possible to connect a plurality of transmitting stations.

Furthermore, in this embodiment, as shown in FIG. (shorter than the signal length).

This makes reading each data bit signal more reliable and prevents communication errors.

Note that when the above-mentioned transmission end signal is defined in a non-pulse state, its length must be longer than the pulse signal interval length in the cheetah binod sequence.

Further, in this embodiment, the reference pulse signal is also used as the transmission start signal, but other than this, a specific pulse signal may be defined as the transmission start signal. The transmission end signal may also be defined using another specific pulse signal instead of using a non-pulse state.

Note that, except during communication, the data bus wire 5 may be set to L level and the take to be communicated may be outputted at H level.

Further, the receiving stations 3 and 4 set a pulse signal whose pulse width is longer than twice the pulse width of the reference pulse signal to "0", and set a pulse signal whose pulse width is shorter than twice the pulse width of the reference pulse signal to "0".
It may be received as 1”.

Effects of the Invention As described above, the present invention enables data bit sequences to be expressed by a magnitude relationship between a pulse width that is an arbitrary multiple of the pulse width of a reference pulse signal and a pulse width of a pulse signal representing a cheetah binod, thereby allowing communication between stations with different system clocks. However, it is possible to communicate over a 1-line line, and multiple transmitting stations can be connected by indicating the start and end of transmission. If the pulse width is longer than the pulse width,
The pulse width of the short pulse signal is made shorter than the pulse width of an arbitrary multiple of the pulse width of the reference pulse signal, and the receiving station receives a pulse signal whose pulse width is longer than the pulse width of an arbitrary multiple of the pulse width of the reference pulse signal by "1". °, and a pulse signal with a pulse width shorter than an arbitrary multiple of the pulse width of the reference pulse signal is “0”.
”°, and any of the pulse widths of the said pulse signal at the boundary between the pulse width of an arbitrary multiple of the pulse width of the reference pulse signal output by the transmitting station, the pulse width of the long pulse signal, and the pulse width of the short pulse signal. By providing a region where the pulse width is different from that of the reference pulse signal, and by providing a clear difference between the pulse width of the long pulse signal and the pulse width of the short pulse signal, which is an arbitrary multiple of the pulse width of the reference pulse signal, communication can be ensured without data errors.

[Brief explanation of the drawing]

Fig. 1 is a flow diagram of a communication device in an embodiment of the present invention, Fig. 2 is a waveform diagram during data bus wire communication in an embodiment of the invention, and Fig. 3 is a conventional two-line communication system. System professional using. 4 is a block diagram of a system using the conventional one-line communication method, and FIG. 5 is a waveform diagram during communication between the data bus wire and the clock wire in the conventional transmission method. 12...Transmitting station, 3.4...Receiving station,
5...Data bus wire. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) A plurality of stations are connected by a single line, a data wire is provided for transmitting a data bit sequence between at least one transmitting station and at least one receiving station, and the data wire is connected to a data bus. a data bit sequence consisting of a reference pulse signal followed by a long pulse signal longer than an arbitrary multiple of the reference pulse signal length and a short pulse signal shorter than an arbitrary multiple of the reference signal length; A communication device that sends (2) The communication device according to claim 1, wherein a transmission start signal is sent before the data bit sequence, and a transmission end signal is sent after the data bit sequence. (3) The communication device according to claim 1 or 2, wherein the pulse interval is set to a length different from the length of any pulse.