FR2643207A1 - Communication system for fax - Google Patents

Abstract

A fax machine 2 and a host computer 1 are connected by a data transmission link which normally operates at slow speed. The modems of the computer and of the fax machine are switched to a high-speed data transmission mode after confirming the transmission of an appropriate signal, so that control data can be transferred rapidly from the host computer to the fax machine so as thus to fix various functions of the fax machine without manual intervention.

Description

COMMUNICATION SYSTEM FOR TELEC: OPIE
The present invention relates to a communication system for facsimile, and more particularly relates to a communication system for facsimile of the type in which a host computer is connected to a facsimile apparatus which constitutes a terminal of this computer, in accordance with a procedure for controlling the transmission of a binary code signaling system, control data are allocated to a predetermined field in an HDLC frame which constitutes control signals used in the host computer and in the facsimile machine, and the control data thus allocated is transmitted to the facsimile apparatus, thereby enabling any function in the facsimile apparatus to be set and changed from the host computer.

 A facsimile apparatus has various functions such as a function for recording the origin of a communication and an automatic dialing function. In general, these functions are fixed using input keys (such as a numeric keyboard and function keys) on a control part of the facsimile machine. It is normally difficult for a user to set the functions described above, which means that a technician must travel specially to the user for this purpose, which is very inconvenient.

 To solve this problem, there has been previously proposed a process in which a facsimile machine is connected to external terminals of a computer or the like by means of telephone lines, so that various functions of the machine fax machine can be fixed through the computer terminals.

 With a process like the one described above, it is obviously unnecessary for a technician to come to a user's home. This process is, however, accompanied by the following problem: when fixing the functions requires a large amount of control data, considerable time must be devoted to fixing the functions.

 The object of the invention is therefore to solve this problem and to provide an efficient method which makes it possible to fix the functions of a facsimile machine in a short time, even if a large number of control data are necessary to fix the functions of the fax machine.

To achieve the above object, the invention provides a facsimile communication system of the type in which a host computer is connected to a facsimile apparatus, constituting a terminal of the computer, in accordance with a transmission control procedure. of a binary code signaling system, and control data are allocated to a predetermined field in an HDLC frame which must constitute control signals used in the host computer and in the facsimile machine, to transmit this data to the fax machine, thanks to which any internal function of the fax machine can be set and changed from the computer, characterized in that the host computer as well as the fax machine fax machines are respectively equipped with at least one modem which is capable of transmitting and receiving signals at a first modulation speedX demodulation and at a second speed modulation / demodulation signal higher than the first modulation speed, t demodulation, each modem which is used for the host computer and the facsimile apparatus normally performing signal transmission at the first modulation / demodulation speed and being switched towards the second modulation / demodulation speed after receiving a "ready to receive" signal, or under the effect of the transmission and / or reception of a frame
HDLC including control data, following the transmission of the "ready to receive" signal.

 Although the transmission of information is performed between the facsimile machine and the host computer in accordance with the transmission control procedure of the binary code signaling system, when the host computer applies a signal to the facsimile machine "ready to receive" (hereinafter abbreviated as "CFR"), the command data (the amount of information that the host computer must process is very important in comparison with other signals) rewrite by the host computer are transmitted as a result.

 Since the modems of the host computer and the facsimile apparatus are switched to fast transmission after confirmation of transmission and reception of the CER signal in the present invention, control data can be transmitted and received in a short time, despite the presence of a large amount of control data, and the functions of the facsimile apparatus can thus be fixed.

Other characteristics and advantages of the invention will be better understood on reading the description which follows of an embodiment, given by way of nonlimiting example. The following description refers to the accompanying drawings in which
Figure 1 is a block diagram showing a hardware which includes a host computer and a facsimile apparatus, to which a communication system according to the invention is applied
Figure 2 shows an HDLC frame format
Figures 3 and 4 are diagrams of a sequence of signals; and
Figures 5 to 10 are flowcharts which describe an embodiment of a system according to the invention.

 FIG. 1 shows the structure of a hardware which comprises a host computer 1 and a facsimile machine 2 to which a system according to the invention is applied. The host computer 1 comprises a central processing unit 3, a read-only memory 4, an internal memory 5, an external memory 6, such as a floppy memory, a character generator 7 intended to produce a configuration of character bits, a character code generator 8, an input unit 9 such as a keyboard, a display unit 10 such as a CRT screen, a printer 11, a modem 12, a network control unit 13 used to provide a line control function, and a telephone set 14.

 On the other hand, the facsimile machine 2 comprises a central unit 21, a read-only memory 22, a random access memory 23, an original reader 24, a control panel 25, a recording device 26 such as a thermal head, an HD type switch 27, a modem 28, a network control unit 29- and an automatic numbering device 31.

 The two modems 12 and 28 which are used respectively for the host computer 1 and the facsimile machine 2 described above make it possible to demodulate signals at a modulation / demodulation speed (first speed) of 300 bit / s , and at a modulation / demodulation speed (second speed) from 2400 bit / s to 9600 bit / s. In addition, the host computer I is connected to the facsimile machine 2 by means of a communication line 30.

The host computer 1 and the facsimile machine 2 have been constructed so that they can communicate with each other in accordance with the transmission control procedure of the binary code signaling system based on CCITT recommendation T-30.

The binary code signaling system refers to the transmission control procedure which is mainly suitable for the G3 type device. The signal sequences are analogous to those used in a multi-frequency signaling system. However, this system uses a number of control signals and allows for improved operations. The control signals that are used in the binary code signaling system are all established as part of an HDLC frame, and the system provides transmission and reception of the control signals. Figure 2 shows a basic format of the HDLC frame for control signals.The frame is based on the CCITT recommendation T-30, and is formed by a structure in which many fields such as a preamble field and a flag sequence field are placed longitudinally, continuously. Among these fields, a facsimile control field (FCF) contains control signals such as DIS and CSI signals appearing in a table presented below. A facsimile information field (FIF) following this field contains additional information to describe in more detail the control signals of the FCF field. Control data which must be set in the facsimile machine from of the host computer are contained in the FIF field in a frame
HDLC predetermined, and transmission and / or reception of control data is performed between the host computer and the facsimile apparatus.

 Figures 3 and 4 are signal sequence diagrams showing procedures that are used to secure various functions of the facsimile apparatus using the host computer. FIG. 3 shows a procedure for reading, by means of the host computer, functions which have already been fixed in the facsimile apparatus. Figure 4 shows a procedure for writing new functions. The read procedure which is shown in FIG. 3 is necessary to determine whether or not control data is written to certain addresses, and also to determine whether the writing of data has been carried out correctly or not, after the completion of writing data to associated addresses. The table below shows the content of each of the control signals which are represented in FIGS. 3 and 4.

Board
Control signal Content
DIS Digital identification signals representing
that the device to be called has a reception function
tion based on standard- CCITT
CSI Identification signals for terminals with
call
NSF Signals for identifying functions beyond
limits of the CCITT recommendation (if
non-standard function identification)
NSC Numerical orders to react to information
contained in NSF signals (identi
fication of non-standard function orders)
NSS Command signals to represent functions at
set among non-standard functions represented
sensed by NSC and NSF signals
TCF Signals to determine the learning of the modem
and to check if channels can be used
whether or not read at the transmission speed of the
modem
CFR Response signals to represent the authorized
start message transmission
after completion of the necessary procedures
PPS Signals to represent the. end of a format of
partial page with messages or format
full page with messages
EOP Signals to represent the end of the transmission
pages with messages, and freedom
to carry out a subsequent information transmission
superior
CFR Signals to represent that messages have
been fully received, in accordance with the re
positive response corresponding to EOP.

FIGS. 5 to 10 are flow diagrams relating to the accomplishment of the procedure corresponding to the signal sequence which is represented in FIGS. 3 and 4. In the drawings, FIG. 5 is a flow diagram which describes the operation to be carried out side of the host computer. FIGS. 6 and (are flowcharts which describe a subroutine by means of which the operations based on predetermined steps of FIG. 5 have been described in detail. FIG. 8 is a flowchart which describes the operation to be carried out on the side of Fig. 9 and 10 are flow charts for describing subroutines corresponding to predetermined steps in Fig. 8. First, when a call number is dialed from the computer side host (hereinafter called "Caller Side'5 and is directed to the side of the facsimile machine (hereinafter called" Called Side "), a timer T1 is set to a certain value, in accordance with recommendation T-30 of
CCITT, and then it starts counting the elapsed time (S2). When a call to the called side is made by the calling side, a duration is set in the same way in timer T1 (S61), and each of the NSF, CSI and DIS control signals is sent to the calling side ( S62). All control signals are fixed based on the HDLC frame structure. At this time, the modulation / demodulation speeds of the modems which are used for the facsimile machine and for the host computer have been fixed at 300 bit / s.

The calling side reacts to the CSI command signal described above by confirming a telephone number on the called side (S6). It also determines, on the basis of an NSF signal (S71 whether the called side includes or not functions which are capable of carrying out the fixing of control data by remote control. In the case where the called side includes these functions, when 'you want to read a configuration from the called side, the calling side sends an NSC signal to the called side (S9). When the called side receives the NSC signal, the program goes from Step S65 to Step S66, and the the subroutine shown in FIG. 9 is executed. When it is found under the effect of the execution of this subroutine that the signal is a configuration read command, the program proceeds from Step S81 to Step
S82.This has the effect of fixing a memory zone in which a configuration has been written (S8), and therefore of transmitting an NSS signal (S83). When the calling side receives this signal, the program goes from Step S10 to step Sol2. Incidentally, it is noted that, in this case, when the NSS signal is not received during the duration which has been set in the timer
T1, the program goes to Step Sll, at which an error processing is carried out. On the contrary, when the NSS signal is received for the duration which has been fixed in the timer T1, it is carried out at Step. SI2 an exploration of an address table corresponding to the configuration to be read, and the program then proceeds to. Step 814, through Step S13.

The procedure of step S14 corresponds to a subroutine which is shown in Fig. 7. Data addresses to be read and the number of bytes are set here after the reception of the NSS signal from the called side has been confirmed ( S41), and an NSC signal is sent to the called side. When the called side has received this NSC signal, the routine of Step S66 is executed again. In other words, the program on the called side goes from Step S81 to Step S84, and the addresses present in the configuration field which has been set in Step 582 are then checked. When the reading of the information which has been written to the addresses is prohibited by the switching of the HD switch 27 which is incorporated on the called side, a prohibition indicator is set (S85) and the NSS signal is transmitted (S83) A little later, the connection line is placed in a disconnected state. On the contrary, when the above relation is reversed, the program goes from step S84 to steps S86 and S87.

In addition, desired addresses and byte numbers are stored in a data section for the NSS signal, and are temporarily stored in a transmit buffer. The recorded information is supplied to the calling side, together with the NSS signal (S88). A TCF signal for controlling the learning of a modem is also provided in conjunction with the ISSUS signal (su9), The TCF signal is transmitted at high speed for subsequent confirmation for the transmission of command data at high speed . Incidentally, it will be noted that the steps intended for processing the data to be transmitted and / or received at high speed are represented by a box drawn with double lines, as in Step S89.

 When the calling side receives the NSS signal from the called side, the program proceeds from Step S45 to Step S46. At this time, when addresses contained in the configuration field to be read are subject to a read prohibition, under the effect of the switching of the HD switch 27 g-z is incorporated on the called side, the processing of line disconnection is performed. On the contrary, when no prohibition is imposed, the program proceeds to Step S47. At this stage, a check is carried out to determine whether the demodulation / modulation action can be performed or not at high speed, on reception of a TCF signal.

When it is possible to perform the demodulation / modulation action of the modem which is incorporated in the calling side at high speed, a learning failure signal (FIT) is produced (S48). On the contrary, when it is possible to perform the demodulationtmodulation action at high speed, a CFR signal is emitted (S49).

 When the called side does not receive a CFR signal, it is considered that learning has failed. As a result, the modem speed is reduced in Step S91, and the modem learning attempt is made again (S92). On the contrary, when the CFR signal is received, the program proceeds to Step S93, at which data to be read by the calling side is provided in the next step. In this case, the transmission procedure is implemented in accordance with the ECM procedure based on CCITT recommendation T-30. In addition, the modem processing speed is high in this case. Consequently, the data can be transmitted in a short time despite the presence of a large amount of data. When predetermined data has been fully supplied, the PPS and EOP signals are transmitted (594). On the effect of the transmission of these signals, the mode is switched to low speed. Then, the mode always remains at low speed until the TCF signal is produced. The called side is placed in a standby state until the calling side provides an MCF signal (S95). If this MCF signal is applied, the program goes to the return phase. Otherwise, the operation described above is performed repeatedly (S94, S95), until the number of repeated attempts becomes greater than a predetermined value (S96).

 When the calling side receives data which is supplied by the called side and then receives the PPS and EOP signals, an MCF signal is sent, which indicates the completion of a read operation. Incidentally, note that the procedure for receiving data at Step S50, on the calling side, which was based on the ECM procedure in accordance with CCITT recommendation T-30, is identical to the associated procedure for providing data on the side. called. In addition, after all the read data has been received1 the modem which is incorporated on the calling side is switched to low speed. The switching to low speed can be determined on the basis of the PPS and EOP signals.

 We will now describe a procedure for setting functions on the called side, starting from the calling side. In this case, the processing in the procedure in which a call is directed from the calling side to the called side, whereby the NSF, CSI and DIS signals are provided by the called side, is the same as in the present case. above, and its description is therefore omitted. When each of the NSF, CSI and DIS signals is supplied from the called side, the calling side does not emit an NSC signal relating to the called side, since it has been placed in a mode in which control data is to be As a result, the calling side program proceeds from Step S8 to Step S15, through Step S13, after which the subroutine shown in Fig. 6 is executed.

In other words, it is first confirmed whether or not the NSF signal has been received from the calling side (S21). Addresses relating to the control data which it is desired to write, and their number of bytes 3 are added to an NSS signal (S23), and the NSS signal accompanied by the information added to it is supplied to the called side (S24). Following the transmission of this NSS signal, a TCF signal is also applied to the called side. This TCF signal is used to determine the need to learn the modem which is incorporated in the equipment on the called side, and to control whether its channel can be used or not at high speed, and this TCF signal is therefore transmitted with a speed high.

 When the NSS signal is received from the called side, the program proceeds from step S67 to Step S68, in which the subroutine shown in Fig. 10 is executed. In other words, the called side checks each address which must be the subject of a writing operation by the calling side. If it finds that it is a forbidden region, the processing for disconnecting the line is carried out (S100). If not, it is determined whether or not the called side can receive the next TCF signal at high speed, which is in synchronism with that which is used on the calling side (S101). If it is not possible to receive at high speed on the called side, an FTT signal is sent and the program returns in order to carry out the learning operation of the modem again. reception possible at high speed, ie reception mode is changed to high speed mode, and a CFR signal is supplied to the calling side (SI03). When the calling side receives the CFR signal, the program proceeds from Step S26 to Step S29, and control data which is to be written to the called side is sent to the latter. At this time, the transmission of this data is carried out at high speed and the transmission procedure is in accordance with the ECM procedure based on CCITT recommendation T-30. After completion of the transmission of control data, the mode is switched to the low speed mode, and the PPS and EOP signals are also transmitted to the called side (S30).

 When the called side receives at high speed the control data which is transmitted from the calling side, based on the ECM procedure (S104), the control data is written to specified memory regions. As described above, the functions on the called side are set in accordance with the data (SI05). When the called side receives the PPS and EOP signals (S106), an hSCF signal is sent to the calling side (S107), which leads to the return operation. After the calling side has received the MCF signal (S31), a DCN signal is sent to disconnect the line. If the MCF signal is not received, the operation described above is performed repeatedly (S30, S31), until the number of attempts becomes greater than a predetermined number (S32). DCN is received on the called side (S69), the called side also performs line disconnection processing.

 According to the invention, and as described above, it is possible to fix and change any function of the facsimile machine, from the host computer which is installed in one location, and there it is not necessary for a technician to come to a user's home.

This system is therefore extremely convenient to use. In addition, since the control data to be fixed is transmitted at a high speed by switching the modems to a high speed, the data can be sent in a short time despite the existence of a large amount of data, which provides good efficiency. More specifically, the time saved can correspond to the 1/8 ratio when the modulation / demodulation speed of the modem is switched from a speed of 300 bits / s normally used to a speed of 2400 bit / s, which means that the efficiency can be greatly improved. Incidentally, it is noted that when the mode is fixed at a modulation / demodulation speed greater than 2400 bits, one can obtain an even higher time saving, exceeding 1/8.

 It goes without saying that numerous modifications can be made to the device described and shown, without going beyond the ambit of the invention.

Claims (1)

CLAIM  1. A facsimile communication system of the type in which a host computer is connected to a facsimile apparatus which constitutes a terminal of that computer, in accordance with a procedure for controlling the transmission of a binary code signaling system, and control data are assigned to a predetermined field in a frame HDLC defining control signals which are used in the host computer and the facsimile apparatus, thereby to transmit this data to the facsimile apparatus, whereby any function internal to the facsimile apparatus can be fixed and changed from the host computer, characterized in that the host computer and the facsimile apparatus include at least one modem each which is capable of transmitting and receiving signals at a first modulation / demodulation speed or at a second modulation / demodulation speed which is higher than the first modulation / demodulation speed, the modem (s) which are used for the host computer and for the facsimile machine normally transmitting a signal at the first modulation speed / demodulation, and being switched to the second modulation / demodulation speed after receiving a "ready to receive" signal, or under the effect and the transmission and / or reception of an HDLC frame containing control data, following the transmission of the "ready to receive" signal.