JPS59153351A - Transmission system - Google Patents

Abstract

PURPOSE:To improve the transmission efficiency by discriminating a transmission level of a signal consisting of at least a ternary level on a transmission line to halve an address discriminating circuit and to reduce an information frame. CONSTITUTION:A data signal on the transmission line is used at least as a ternary level and the signal is made different in level when the inter-station communication or multiple address communication is executed. In case of the latter communication, since the signal level on the transmission line is different from that at the inter-station communication, it is recognized as the multiple address communication. Thus, a transmission station address S-ADR is omitted in the information frame.

Description

Detailed Description of the Invention Technical Field The present invention relates to a transmission system in which a data signal on a transmission line connecting devices is at least three levels, and a communication destination is clarified by 11 degrees depending on the signal level.

BACKGROUND ART Conventionally, signals on a transmission path have been transmitted and received at binary levels indicating presence or absence, and transmission and reception has been performed only by combinations of signal presence and absence, that is, coded signals.

For this reason, multiple devices are connected to a transmission path, and communication between one device and one device (hereinafter referred to as "inter-office communication") and communication between one device and multiple devices (hereinafter referred to as "broadcast communication") is possible. When carrying out "Communication"), the transmission message sent from one device includes a "destination address" that indicates the destination in both inter-office communication and round-trip communication.
) It was necessary to get an A+.

This means that each device must have both its own address during inter-office communication and its own address when communicating (M), and it must also have an address discrimination circuit when communicating with two VCs at 1G, resulting in a sloppy configuration. There were drawbacks such as:

Purpose The present invention has been made in view of two points. By using a signal consisting of at least three levels on a transmission path and using f2i signals of different levels when performing inter-office communication or round-trip communication, It is an object of the present invention to provide a transmission method that allows the total width of the address discrimination circuit of each device to be reduced and allows easy discrimination between inter-office communication and broadcast communication.

Embodiment 1 An embodiment according to the present invention will now be described with reference to the drawings. FIG. 1 is a diagram showing a formant diagram and a synchronization level of an information frame transmitted and received via a transmission path.

FIG. 1(A) shows the formant format used for inter-office communication, with PREFLAG indicating the beginning of the information frame and CoNT1 . of control information indicating the beginning of the header. D-ADR1 sending station address fr: 5-
ADR, C0NT2 of control information indicating the beginning of data information
゜Data information TEXT, remove the end of data information C0
NT-3, NAEC Canctor BC for data filling detection
It consists of C and PO8T FLAG which indicates the end of the frame. As shown in FIG. 1(B), the information frame transmits information in one frame with an amplitude between logical values "l" and "o'°.

Figure 1 (H
), the transmission timing is shown in Figure 1 (l and (0). In this way, by setting the transmission (g and bell to three levels), the receiving address can be omitted as shown in Figure 1 (B). That is, according to the present invention, during broadcast communication, communication between stations is possible.
Due to the difference in the signal level on the transmission path at time B, r
Since it is recognized that the FiJ report (8- is a failure), the sending station address 5-ADR can be omitted in the information frame.

FIG. 2 is a block diagram of an embodiment according to the present invention.

In FIG. 2, the signal +il from the transmission line is input to the broadcast/inter-office communication discrimination circuit 4K via the receiver 3 in the receiving device 2, and it is judged whether it is the broadcast communication or the inter-office Jt signal. The control data 5 is sent to the transmission/reception controller 9.

In the case of inter-office communication, the received atlus information is sent to the signal line 29.
The setting address data of the address discrimination circuit 7 via
Address signal discriminating circuit 6 If a match is determined by fC and a match is detected, it means that the frame is being received addressed to the device itself.
is sent to the transmission/reception controller 9. If the addresses do not match, the frame is dead for another device, so no reception operation is performed.

When the transmitting/receiving controller 9 receives the address/mosquito signal 8 from the address signal "r discrimination circuit 6," it starts receiving operation, and receives the receiving control color code 10 so as to store the received data from the receiver 3 in the receiving register 12. As a result, the reception register i2H (stores the primary reception data via the g-1 line 31, FIG.
n PO8T F'LAG detection-i te mata it HC
(The data is stored until the galactor is received. -i [is deleted.) When the frame worth of data is received and stored, the central processing unit b (hereinafter referred to as CPU) 15
The control signal 13 is output to the
'111, the data is taken in again via the data bus 14 and the receiving operation is completed.

If it is determined to be a broadcast communication, the information will be unconditionally received.
1 Since there is peace of mind, rα immediately starts the reception operation, stores it in the reception register in the same procedure as communication between one station, and crt
Shift to control at t15.

Next, the case of transmitting data will be described. CPU15
stores information for l frames to be transmitted in the transmission register 17 via the data bus 16. After storing the data, the CPU 15 transfers the control information 13 to the transmission/reception control. The transmitter/receiver controller 9 sends the control signal 8 to the transmitter register 17 and sequentially receives the transmitter data. (In the controller 9, before sending data to the oil feeding device 24, the sending level is set from the sending level conversion control signal 32in in the case of broadcast communication to the sending level at the time of broadcast communication, and the inter-office communication is 1M
(In case D, the output level is controlled to be the same as that during inter-office communication.

Thereafter, the data is sent to the transmitter 23 via the signal level conversion circuit via the transmission data line 20, and the information is sent out on the transmission path via the data link 25 in the transmitter 23.

A simple embodiment of the receiving device 2 is shown in FIG.

In Figure VC, data from the transmission path is transmitted to the control information discriminator 3.
PREF indicated in the information format of Figure 1 by 5.
Whether LAG is accepted or not f! : being monitored 1,
If reception is confirmed here, the flip-flop 37 is set. When flip-flop 37 is set,
Subsequent reception information is a signal! The address signal +j is sent to the address signal +j discriminating circuit 6 via 29, and it is discriminated whether or not the received addresses match. In addition, the received data is monitored by the comparator 33 of the broadcast/inter-office communication discrimination circuit (the reception level is monitored; for example, in the case of broadcast communication, the output of the comparator 33 is turned on, and then the control 1^ signal discrimination section 35, when the reception of the control IIL, II (g) is confirmed, the transmitting/receiving controller 9 is notified of the reception of the broadcast communication.

When data is to be received, the transmitting/receiving controller 9 outputs the receiving part sub-signal 10, and at the same time the data is stored in the receiving register, the 7-lip 70-tub 37 is reset.

Here, the basic direct voltage generation for the received signals compared with the ratio V was done with an energy diode DI, but it is sufficient to use a constant voltage source. Of course, it is sufficient as long as a comparison reference potential with which a difference can be determined can be obtained. The data transmission level switching force method has several different methods, but since they are common knowledge, their explanation is omitted.

Effects As explained above, according to the present invention, it is possible to determine whether it is broadcast rationalization or inter-office tracing (O) by simply determining the sending level of a signal consisting of at least three levels on the transmission line, so that address discrimination is possible. The effects are tremendous, such as improving transmission efficiency by eliminating circuits and shortening information frames.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the format and transmission level of the information room, FIG. 52 is a block diagram of an embodiment of the present invention, and FIG. 3 is a detailed diagram of the receiving device. In the figure, 2: receiving device, 3: receiver, 4: broadcast/inter-office color discrimination circuit, 7: address setting circuit. 9... Transmission/reception controller, 12... Receiving router,
15-Central processing unit, 17... Transmission lens star, 21.
...Ig signal, bell conversion 1, conversion circuit, 23...transmitter, 24
...Transmission device pupil, 33.-Comparator 535...Control information discriminator. 37...Sorin'nlop.

Claims (1)

[Claims] 1. In a transmission/system in which a plurality of devices exchange information using a common transmission path, the data signal on the transmission path is set to at least three levels, and the information communication is performed according to the level of the data signal S. A transmission method characterized by determining the device that performs the transmission. 2. Claim No. 2 characterized in that transmission is performed by changing the level of a data signal during communication between specific devices and the level of data (m) during communication from a certain device to all connected devices. Transmission method described in Section 1.