JPS6151462B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for interrupting a facsimile transmission procedure, and more particularly to a method for interrupting a facsimile transmission procedure during facsimile communication in a facsimile device equipped with G3 and G2 functions specified by CCITT.

Figure 3 shows an example of the configuration of a transmission control unit to implement a procedure compliant with CCITT's interim recommendation T.30.
The transmission control unit 1 is connected between the modem 2 and an encoding/decoding unit and a system control unit (not shown),
Performs control signal and image information transfer processing. The transmission control unit 1 includes a control circuit 3 that creates a transmission frame based on instructions from a system control unit and decodes a received frame, and an FCS (frame transmission error) that operates based on instructions from this control circuit 3. Check bit for detection) arithmetic circuit 4, 0 insertion circuit 5, F (frame synchronization code)
a generation circuit 6, a multiplexer 7, an F detection circuit 8 for giving instructions to the control circuit 3, a 0 removal circuit 9,
It is equipped with an FCS calculation circuit 10 and the like.

With this configuration, for example, in phases B and D of the facsimile transmission procedure, the control circuit 3 creates control data for configuring a frame based on the control signal from the system control unit, and at the same time, the multiplexer 7 receives the control data. can be switched to the side.
The control data outputted from the control circuit 3 is subjected to a check bit calculation for detecting a transmission error in the calculation circuit 4, and an FCS is added to the control data. Further, 0 is added to the FCS-attached control data by a 0 insertion circuit 5 to clearly distinguish it from the F pattern, and the data is output to a multiplexer 7. The F pattern output from the F generation circuit 6 is added to this data to form a transmission frame, which is sent from the modem 2 via the network control circuit 11 to the other party's facsimile device.

On the other hand, when the F pattern is detected by the F detection circuit 8, the received frame sent from the other party's facsimile device is 0 until the next F pattern is detected.
The removal and FCS calculation are performed by the 0 removal circuit 9 and the FCS calculation circuit 10, respectively. If there is no error in the control data, its contents are decoded by the control circuit 3 and transmitted to the system control section.

In addition, in phase C, during transmission, the transmission image information output from the encoding section is sent to the multiplexer 7.
The received image information is sent from the other party via the modem 2 and network control circuit 11 to the other party's facsimile device, while at the time of reception, received image information sent from the other party is input from the network control circuit 11 and modem 2 to the AND gate 12 to the decoding unit. .

In this way, the facsimile transmission procedure is executed via the transmission control unit 1, and the devices connected to the line sequentially advance the control sequence in accordance with the transmission procedure, thereby performing mutual facsimile communication.

The above is a description of the well-known transmission control unit.
In such a transmission control unit, if the facsimile transmission procedure according to CCITT regulations is interrupted, G3
DCN (line disconnection command) in functional mode, PIS (procedure interruption signal) in G2 functional mode
It is stipulated that the suspension shall be suspended.

Therefore, it is a facsimile machine that has both G3 and G2 functions (hereinafter referred to as G3 + G2 machine).
In this case, after identifying the function of the other party and setting the mode according to the function of the other party, there is no problem because the facsimile transmission procedure can be interrupted based on the above regulations.

However, if the procedure is interrupted before the mode is set, that is, before handshake with the other party is established, there is a problem in that it is not possible to determine whether to send DCN or PIS because the other party's function is unknown.

That is, Fig. 1a shows a general facsimile transmission procedure in phase B when G3+G2 machines are on the calling station side, but as can be seen from this flow diagram, If the procedure is interrupted before the function of
As shown in c, only when the line is disconnected and the other party's function can be identified, that is, after handshake is established, depending on whether the called station has G3 function or only G2 function, after sending DCN as shown in c, Either the line is disconnected, or the line is disconnected after the PIS is sent as shown in d. In addition, the procedure branch R in the figure
1 shows a case where the calling station moves to a procedure for receiving a facsimile message.

Therefore, for example, if a G3+G2 machine is on the called station side and the procedure is interrupted before handshake is established,
Since the called station does not send an interrupt command, the calling station has to disconnect the line based on its own transmission procedure, and during this time it has to pay unnecessary line usage fees, resulting in a disadvantage. There were some inconveniences such as suffering from

In view of the above points, it is an object of the present invention to provide a method for interrupting a facsimile transmission procedure in which the other party's machine can interrupt the procedure based on an instruction from the G3+G2 machine even before the handshake is established.

To achieve this objective, the present invention combines PIS and
The feature is that the DCS is sent out in series.

Embodiments of the present invention will be described below with reference to the drawings.

For example, if the G3+G2 machine interrupts the facsimile transmission procedure shown in FIG. 1 a above, in this embodiment, as shown in FIG. 2,
After sending DCN and PIS, disconnect the line.

Of course, in this case, the sending order of DCN and PIS can be set arbitrarily. Furthermore, it goes without saying that the facsimile transmission procedure is not limited to this, and there may be other types, such as when G3+G2 machines are the called stations. Furthermore, it goes without saying that the procedure during facsimile communication may be interrupted at any time due to operator actions, machine circumstances, etc.

In this way, when the G3 + G2 machine side interrupts the procedure, by disconnecting the line after sending DCN and PIS, the other machine can
The line can be immediately disconnected based on instructions from the G3+G2 aircraft.

As a result, for example, if the G3+G2 machine is on the called station side,
Moreover, even if the G3 + G2 machine encounters a problem and the procedure is interrupted before handshake is established, the PIS and DCN are sent back to the calling station, so the line can be immediately disconnected, eliminating wasted time. No need to pay line usage charges.

In this case, if the handshake is established and the partner's function is identified, the procedure is interrupted.
Even if PIS and DCN are sent, no problem will occur to the other device. Moreover, by sending PIS and DCN, there is no need to change the interruption procedure before and after handshake establishment, which has the advantage of simplifying the software.

As described above, according to the present invention, when the G3+G2 machine interrupts the facsimile transmission procedure, the PIS,
Since both DCN and DCN are sent, the other party can immediately disconnect the line based on instructions from G3 and G2 even before handshake is established.

[Brief explanation of the drawing]

FIG. 1a is a general flow diagram showing an example of a facsimile transmission procedure in G3+G2 machines, b to d are conventional procedure interruption flow diagrams in the flow diagram, and FIG. FIG. 3, a procedure interruption flowchart showing an embodiment, is a block diagram of a conventionally known transmission control section. A to E...Branch, T...Sender flow, R...
Receiver flow.

Claims (1)

[Claims] 1. In a method for interrupting a facsimile transmission procedure during facsimile communication in a facsimile device equipped with two functions, G3 function and G2 function that comply with CCITT, at least the function of the other party before handshake establishment is one of the above two functions. If it is necessary to disconnect the line while the transmission procedure is being executed, the procedure interrupt signal PIS used in the above G2 function mode and the line disconnection command DCN used in the above G3 function mode are sent. A facsimile transmission procedure interruption method characterized by transmitting a signal together with the line and disconnecting the line.