FR2524233A1 - MODEM AND METHOD FOR CONNECTING A MODEM INTO A CHOSEN CONFIGURATION - Google Patents

Abstract

THE INVENTION RELATES TO THE CONNECTION OF MODEMS FOLLOWING VARIOUS CONFIGURATIONS. A FRONT PANEL 10 ALLOWS ENTRY SIGNALS TO BE ENTERED INTO THE MODEM 12 WHICH INCLUDES A FIXED MEMORY 46 INTENDED TO RECORD INFORMATION CORRESPONDING TO ONE, SELECTED, OF SEVERAL POSSIBLE CONFIGURATIONS OF THE MODEM, A MODIFIABLE MEMORY 44 DESTINED TO REGISTER INFORMATION CORRESPONDING TO SEVERAL CONFIGURATIONS OF THE MODEM, AND A PROCESSOR 30 WHICH REACTS TO THE INPUT INFORMATION AND WHICH CONTROLS, BASED ON THIS INFORMATION, THE PASSAGE OF SELECTED DATA FROM THE FIXED MEMORY INTO THE MODIFIABLE MEMORY AND, THEREFORE, THE CONFIGURATION OF THE MODEM DEPENDING ON THE INFORMATION CONTAINED IN THE MODIFIABLE MEMORY. FIELD OF APPLICATION: TRANSMISSION OF DIGITAL DATA.

Description

The invention relates to the field of modulators / demodulators (modems

used for the broadcast and the

  receiving digital data).

  In the prior art, it is common to manually connect a modem in a particular mode of operation or configuration. Examples of such modes of operation or configurations include speed, multiple access, half duplex, or duplex. integral, point-to-point or multipoint mode, central or remote modem mode, etc. For example, U.S. Patent No. 4,270,202 discloses a dynamic access embodiment of the "dynaport" type in a multi-access modem mounted on a data line

to modem.

  The increasing complexity of modem design results in an increase in the number and

  the complexity of the connections to be established during the

  installer and / or operator to meet the demands of various modem users in different configurations and uses of modems. which results in a loss of data transmission time It has been possible in the past to make very limited modifications to the configuration of modems which are subject to connection modifications, by means of switches operated by buttons. eg push-buttons, placed on the front panel of the modem to change, for example, the modem working speed, in bits per second The switches are connected by a fixed wiring to an appropriate part of the internal circuit of the modem so that the we can make the change

  desired, for example concerning the speed of the modem.

  In the past, it has been common to arrange modems in a network equipped with a controller whose example

  is given in the United States patent application

  No. 265,175, filed May 19, 1981 under the title "Modem Diagnostic and Control System" by Arthur H Rosbury et al. Modems are equipped with a circuit that controls the status of modems and working parameters

  and which transmits this information to the network controller.

  It is also common for the network controller to poll the network modems and control the transmission.

  to the status and parameter information controller.

  The network controller is also used to receive indications of the failure of one or more modems in the network and to control the execution by a modem of selected test programs and the transmission of the results of these programs to the controller. has been done in the past through a telemetry link using a low data rate,

  for example 75 bits per second and, for example, a trans-

  Frequency shift keying data mission on a portion of the transmission line connecting the modems and the network controller, which is not used for transmitting the higher speed data

  for the transmission of which the modems are used.

  The display on the network controller of the status and configuration of remote modems located in the network is therefore possible, as well as the display of the results of the control test program carried out by the remote modem II. has often seemed desirable to allow

  to modems on the transmission link-

  to query the status and configuration of other modems in the transmission line

  and to trigger a test on another modem, without

  network controller, or to be informed of the malfunction conditions of a remote modem.

  particularly without such intervention.

  It has also appeared necessary, in this field, to have means for modifying the configuration of a modem without cutting off the power supply.

  and to make connection changes without

  ruption, so as not to interrupt the transmission of data It is also desirable to be able, from a modem, for example in the first place, to change the configuration and connection of remote modems

  located on the same data line.

  The invention therefore relates to a modem, for example

  placed in a data line, which includes a

  input device located on the outside of the modem chassis, for example the front panel, and an associated display device The input device and the display device are connected to a microprocessor

  or other suitable data processing unit

  cooked to full scale integration, having a memory

  The memory can be a read-only memory

  electrically modifiable remanent grammable, for example of the type ER 1400 produced by the firm General Instruments, or, alternatively, such an electrically modifiable remanent read-only memory and a fixed read-only memory The microprocessor or other suitable unit of data processing circuit and large-scale integration may also be connected to an external control signal input source, for example a centrally located network controller, another mddem on the data line, or a terminal processing equipment data (DTE) placed on the

data link.

  A feature of the invention is that an intervention on the connections is provided entirely by the software by means of a microprocessor incorporated in the modem, and an associated memory The connection microprocessor cooperates with other microprocessors or circuits large-scale integration in the modem to establish the configuration of the modem.

  microprocessor connection is accessible at the location-

  modem using an interface allowing the operator to

  to communicate with the connection microprocessor and the associated memory via an input and display part located, for example, on the front panel of the modem. Using the front panel, the operator can order the display of the configuration of the current connections, the implementation of the

  control of some normal preselection

  or special connection, performing minor changes to special configurations or

  preselected standards, or any

  special, all possible configurations of -connections All these operations can be performed

  both at the time of manufacture and installation

  to quickly and accurately establish the

  Thus, the connections can be modified from one modem to another using the present invention. control panel can be executed from the front panel and from one modem to the other, without the need for a network controller or data terminal equipment. However, these elements can also be used to control and control tests and status reports, or to perform connection changes on remote modems Modems on the data link can therefore have their configuration modified quickly and accurately, for example, without that their food is cut off and with a very

  low or zero data transmission.

  The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting example and in which:

  FIG. 1 is a view of the front panel of a

  modem 'according to the invention, constituting the input interface to the connection microprocessor, this panel also comprising a display board, Figure 2 is a simplified diagram of the modem according to the invention; Figure 3 is a simplified diagram showing the interconnection of various processors in the modem according to the invention;

  FIG. 4 is a simplified diagram of a micro-

  a processor optionally usable in the present invention, and its interface through the front panel or from remote locations; and figure 5 shows the functioning of the visual

of the modem according to the invention.

  FIG. 1 shows a modem front panel 10. This front panel 10 comprises a part 14 of

  control and a viewing portion 18 having a plurality of

  7-segment digital display elements 20 consisting of, for example, liquid crystal elements or light-emitting diodes. The front panel 10 also has, on the display part, indicator lights 22 giving the "local" indications. ,

  "try" and upright ", an increase command button 24

  In addition, LEDs 28, associated with the display panel 18, indicate, in some cases, the information displayed on the display.

this table 18 of visualization.

  FIG. 2 shows the front panel connection and a test, data rate, and configuration microprocessor located within the modem 12 according to the invention. The modem 12 is of a type in which the The reception and transmission of digital data is carried out by software on a transmission line 32 of a known type and described, for example, in US Pat. No. 4,044,307 and US Pat. US Patent Application No. 304,007, filed September 21, 1981 by Kromer III, under the title "Simplified Digital Data Receiver Apparatus". Modem 12 includes a form-receiver portion which processes input data according to a reception program 36, for example to demodulate, descramble and decode these data, to form a message that is transmitted by a remote modem or a data terminal equipment The modem 12 also includes a portion 38 -formant transmitter which processes the output data by modulating, coding and scrambling them in accordance with a transmission program. The modem 12 can also have several accesses allowing the multiplexing of the data transmitted or received via these accesses. being ordered by the party

42 with multiple access.

  The microprocessor 30 for testing, data frenauence and configuration ("option microprocessor") is accompanied by a memory 44 which may, for example, be a volatile random memory. In addition, a read-only memory

  fixed 46 is connected to the option microprocessor 30.

  The part between the microprocessor of op-

  30 and the other microprocessors of the modem 12 described by way of example herein are shown in more detail in FIG. 3 The modem 12 shown comprises a control microprocessor 41 which, in addition to the interconnections shown in FIG. also has the function of implementing the programs 36 and 40 of the transmitter and the receiver to control the modulation

  and the demodulation of transmissions inside the modem.

  A microprocessor 42 with multiple access and a microprocessor

  43 of transmission are also represented.

  transmission processor is used to perform various control programs in the modem and also to assume remote modem control functions, by

  example as described in aforementioned application No. 265,175.

  A common bus 45 connects these microprocessors 30, 41, 42 and 43 to a random RAM 47 to one byte (8 bits). Information is exchanged between these microprocessors.

  , 41, 42 and 43 via the RAM 47.

  In addition, the microprocessor 41 of the modem controller

  produces an OCENA validation signal applied to the micro-

  option controller processor 30 and a signal from

  MPENA multiple access validation and a validation signal

  TXENA transmission respectively applied to microprocessor 42 of the multiple access controller and microprocessor 43 of the transmission controller, and the option controller microprocessor 30 also produces a TXENA transmission enable signal and an access enable signal. multiple MPENA applied to the microprocessor 42 of the multiple access controller and the microprocessor 43 of the transmission controller for

  allow access to the common bus 45.

  At any time, a single microprocessor 30, 41, 42

  or 43 is authorized to access the common bus 45

  processor 41 of the modem controller communicates with the microprocessor 42 of the multiple access controller once per baud to, on the one hand, transmit data from

  reception and, on the other hand, receive transmission data.

  It also communicates with the microprocessor 43 of the transmission controller once every 32 bauds to receive analog parameter control and

  transmit an analog parameter response The micro-

  processor 41 of the modem controller validates the micro-

  the option controller 30 via the OCENA signal for, for example, 60As at each baud, which allows the option controller microprocessor 30 to exert a control action on the common bus to exchange a connection information and / or status or test information with the microprocessors 41, 42 and / or 43 via the RAM

  47, to perform a read and / or write operation.

in the RAM 47.

  The software protocol is based on a byte.

  A complete exchange of information includes, first,

  an exchange of orders or requests between two micro-

  processors and then an exchange of data or answers.

  For example, the option controller microprocessor 30 may transmit a request to the multiple access controller microprocessor 42 through random access memory 47 to transmit the status of one of the plurality of access controllers.

  access, for example access A, of the multi-access set

  This is followed by a request or command from the microprocessor 42 of the multiple access controller, if that request or command is at that time ready to be communicated to the microprocessor 30 of the option controller, for example a read request and issue of the

  current configuration of the clock connections of the transmitter

  as stored in the electrically modifiable ROM 44 These two requests are separated from one

  time interval chosen in advance, for example 50 as.

  After another preselected time interval, for example 8 bauds, the option controller's microprocessor responds to the clock connection status of the transmitter.

  having located this data in the appropriate position

  memory 44, and the microprocessor 42 of the multiple access controller transmits the access state

A, for example 50as later.

  There are some possible exceptions to this

  protocol, for example exchange of data and

  analog meters between the microprocessor 41 of the modem controller and the microprocessor 42 of the multiple access controller, or the microprocessor 43 of the transmission controller For example, at each baud, the microprocessor 41 of the modem controller requests the data transmitted by the microprocessor 42 of the multiple access controller and

  after a chosen delay, for example 40 as, the micro-

  multiple access controller processor transmits the

  data transmitted to the microprocessor 41 of the modem controller.

  In another example, at each baud, the microprocessor

  the modem controller transmits the received data to the micro-

  processor 42 of the multiple access controller, none

  response is then requested to this microprocessor 42.

  A final example is that in which the microprocessor 41 of the modem controller, for example once every 32 bauds, transmits a request to the microprocessor 43 of the transmission controller, for the analog parameter commands and, after a delay of for example 40 As,

  the microprocessor 43 of the transmission controller trans-

  sets the analog parameter control to the microprocessor 41 of the modem controller This last microprocessor can also transmit to the microprocessor 43 of the transmission controller analog parameter data once every 32 baud, for example, isans

answer needed.

  The microprocessors 30, 41, 42 and 43 can communicate with each other by three different types of requests, namely a read request, a write request and special requests. In a read request, when a microprocessor 30, 41, 42, 43 must obtain data from another microprocessor, it transmits a

  reading request control in the form of one or more

  bytes, with a preselected bit set to 1,

  the most significant bit of the transmitted byte (s).

  In its response interval, the other microprocessor 30, 41, 42 or 43 transmits the data found in the position

  of memory identified by the byte (s) it received.

  Thus, the first microprocessor 30, 41, 42 or 43 actually performs a reading in a memory position of the other microprocessor In the case where a change of state or configuration of system must be transmitted immediately to one or more of microprocessors 30, 41, 42, 43, the other microprocessor 30, 41, 42 or 43 transmits a write command with a preselected bit set to 1, indicating that it In this case, the first microprocessor 30, 41, 42 or 43 does not transmit a response in its response interval, as indicated above, but leaves this interval open for receiving data from of the other microprocessor 30, 41, 42 or 43 However, these two microprocessors 30, 41, 42 or 43 can exchange write commands in the same

  request interval, as previously indicated.

  Special requests may be of the read or write type, all colloquial exchanges falling into this category Examples of special requests include a request for synchronization, a non request for a continuation and action request

  synchronization is used to synchronize the microphone

  processor 41 of the modem controller and the microprocessor of the option controller A non-request is used when the microprocessor 30, 41, 42 or 43 to which an order of requests is transmitted has no current request to be transmitted in its request interval As previously described, a continuation is used when more than one byte of information is requested by the microprocessor 30, 41, 42 or 43 receiving data during the preceding response interval, and it actually extends the previously transmitted request. Intervention requests are used, for example, to trigger a processing cycle in another of the microprocessors, 41, 42, or 43. The response may be an expectation if the processing takes some time, or a special acknowledgment that allows a delay when transmitting the response, if an immediate response is not requested Special responses are returned

  special requests, for example a synchro-

  nonse, a no answer, a hold answer, a write acknowledgment, and a special acknowledgment The synchronization response acknowledges the synchronization request The nonresponse is used in conjunction with the no request The response from Waiting is used in case a processing delay is required The acknowledgment of receipt is sent to acknowledge receipt of a request for writing Special acknowledgments are used with requests for intervention. The table represents the topography of the random access memory according to the invention. As is common for fast memories, each memory position corresponding to the connections J 1 -J 16 has a reading order, for example 80 (in hexadecimal system). and a write command, for example CO, both for J1 in the table, which determines whether it is desired to read what is present in this memory position, or to write it in this

  memory position Each memory position is con-

  bit number byte DO-D 7 D 7 is kept low in each case, this being a means for checking the memory positions, subsequently, in the

case where one byte has been changed.

  All positions J 1-J 16 of the memory of

  connection and some other memory positions possesses

  both the read and write commands The first Ji connection is common to all modem functions and includes standard connection tables and a special connection table for the modem in the modem.

  together, including multi-access

  ples and transmission configurations (remote modem and TX control functions) Thus, the figures

  6-D 4 binaries correspond to modem tables

  stored in a read-only memory 46 which, if called in binary digits D 6 -D 4 in the connection Ji, will be loaded into the positions of the random access memory corresponding to the connections J 2-J 5 By convention, if the digits

  binary D 6-D 4 of the Ji connection are all low, ie

  say 000, no preset configuration of normal modem connections is loaded from the ROM into

  the positions of the random access memory 44 corresponding to J 2 -J 5.

  On the other hand, the state of these memory positions is determined by a table which is introduced into the nonvolatile random access memory 44 which is adapted to the configuration desired by the particular user.

  possible coded designations for configuration tables

  By means of the use of binary digits D 6 -D 4 in connection Ji, namely 001, 010, 011 111 each of these codes corresponds to a preselected normal configuration of connections, having values chosen for each of the binary digits D 6-DO for the connections J 2 -J 5, and each of these tables is recorded as four bytes selected from the read-only memory 46. For example, the modem configuration tables corresponding to the Binary digits 1-7 may comprise (1) a point-to-point configuration with V 27 and V 54; (2) a point-to-point configuration with F L support; (3) a multiple fallout configuration with F L -cantral; (4) a configuration to

  multiple fallout with F L-remote; (5) a configuration

  multiple spillover with V 27-central; (6) a multiple fallout configuration with V 27-far; and (7) a multi-drop configuration with MPS 48-far. The option microprocessor extracts the respective bytes from the read-only memory 46 and loads them into the RAM 44 at the memory locations corresponding to the J 2-J connections. 5, following the decoding of the appropriate table designated by the bits D 6 -D 4 for the

connection Jl.

  Similarly, the fact that the D 3 -D 2 bits are 00 indicates that an adapted, preselected and special multi-access configuration must be used, this configuration being recorded in the RAM

  electrically erasable 44, and this leaves three indica-

  possible coded bytes of selected bytes, in the read-only memory 46 and to be loaded into the memory 44, in positions of the latter corresponding to the three standard versions of connection for the connections J 6-J 12 Thus, the codes 01 , 10 and 11 are representations of a selected group of positions in the

  memory 46, each containing seven bytes of information

  corresponding to a preselected table of values for the binary digits D 6-DO for one of the three preselected normal states possible for the connections J 6-J 12 In the same way, the bits D1-DO, if they are in the state 00, indicate a selection of memory positions containing a suitable table, and if they differ from the state 00, they indicate the location o, in the read-only memory 46, are stored the bytes corresponding to one of the three possible connection configuration tables chosen for connections J 13-J 16 controllers

remote modem / transmission.

  The particular configurations indicated correspond to

  to a "Microzeta" type modem produced by Racal Data Communications, Inc. and, unless otherwise stated, such type is not important to this

  invention is indicated by way of example of an application

  of the present invention to a modem in use.

  As shown in FIG. 4, the micro-

  modem option controller processor 30 includes a central processing unit 60, an input / output interface 62 and an internal RAM 64 The central processing unit 60 can access the fixed read-only memory 46 and the non-volatile ROM programmable, electrically modifiable 44, and is connected via the input / output interface 62 to the front panel 10 and to a transmission line 66 to one or more remote modems 68, a network controller 70 and one or more units 72 of a data processing terminal equipment (E Tr D) are mounted on the transmission line 66. Via this transmission line 66, the option controller can, for example, control a state, trigger a test or establish configurations in

  remote modems 68 and can receive the appropriate commands

  in order to perform the same functions in the modem 12, these commands coming from one of the remote modems 68, the network controller 70 or the data terminal equipment 72 In addition, certain alarm conditions appearing in the local modem 12 are detected by the central processing unit 60 which is programmed

  to display these conditions on a visualization table 18

  and to transmit them via the transmission line 66 to some appropriate remote modems 68, to the network controller 70 and / or the equipment 72 so that their display is carried out on the panel 18

  viewing the remote modem.

  An example of the use of pushbuttons

  16 front panel control is the mode of operation

  After the modem configuration has been established during the manufacture of the installation, using the software configured in accordance with the present invention, if it is desired to modify the configuration, the option microprocessor may be programmed to request the entry of a "key" before allowing any

  modification via the front panel 12.

  -For example, pressing the push button

  marked "*" or "" entry ", the table of

  The display shows "LOG", the blanks indicating numbers from 0 to 9 or indicating, for example, all 0 By pressing the decrease button 24 or the increase button 26, the operator can enter

  a three-digit number in the plans indicated below.

  above, on the scoreboard, ie one digit at a time, from right to left, on the extent of the viewing table 18 The operator then presses again the "input" button and the number of three-digit code is compared to a code stored in the microprocessor memory If the number of code introduced

  is correct, the blocking of the software is invalidated and the operation

  controller can then use other modes, for example

  change configuration or order tests

  status indications to display modem configurations

  12 and parameters can be made without introducing

  code generation Each modem 12 can have its own unique three-digit password code to increase protection against forgery.

  unauthorized transmission network.

  When the "state" button 16 is pressed on the front board 10, the option microprocessor 30 requests the microprocessor 41 of the modem controller the state of the modem speed, the level of reception in the database management. and the quality of the signal, and the table

  18 display is activated to display this information.

  The analog parameter status and the modem test state can also be displayed by successive taps in the corresponding digit pair in Table 18 of Figure 1.

the "status" button 16.

  When the "config" push button 16 is depressed, and when it is desired to check and / or modify the configuration, the option microprocessor 30 addresses a problem.

  RAM position corresponding to a configura-

  designated connection, for example, J 01-J 16 As shown in Figure 5, the display table 18 is operated to display, on the three numbers of

  left, the connection configuration, for example J 05.

  The next digit 20, to the right of 5, has its illuminated central horizontal segment, which means "=" The vertical segments of the remaining four digits are used to indicate the state of the connection stored in the memory for the appropriate connection, that is, J 5 in the table Thus, if we consider the table and FIG. 5, the lower right vertical segment 80 of the rightmost digit 20 in the viewing table 18 indicates that the bit position DO is low in the memory position corresponding to the connection J 5 The upper left vertical segment 82 of the rightmost digit 20 is illuminated, indicating that the bit position D1 is high in the position

  RAM 44 corresponding to the connection J 5.

  Similarly, it can be seen that the bit positions D 6 -D 2 corresponding to the segments 84, 86, 88, 90 and 92 are low. In the case of the connections J 1 -J 16 of the table, the lower left segment the digit 20 to the right of "=" is not lit, because in all connections this position is always set to 0, as indicated by the position D 7 in the table. connection J 5, according to the table, is the transmitter training state corresponding to the selected code 000 The main transmission request is checked in the terminal data processing equipment rather than constantly present The transmitter clock ( TXC) is pre-positioned off rather than on. The selected transmitter clock source is the corresponding one.

  to the code 10, for example an internal clock.

  If it is desired to modify the selected connection to be displayed in Table 18, a flashing floating point 94 may be moved step by step through the display table 18 by depressing the button "16" until this point occupies the position shown in Figure 5 between the element displaying the J and the elements displaying

  the numbers 05 By pressing the 24 button

  the numbers are scrolled to 04, 03, 02, 01, 16, etc. Starting at O 5 and pressing the increase button 26, the numbers go through 06, 07, 08 16.01, 02 etc. Meanwhile, the display of positions

  6 -DO binaries for the memory position changes according to

  to the memory position of the new connection which has been selected to be displayed by scrolling adjacent digits to the letter J. If it is desired to modify one or more of the DO positions of binary digits in the connection memory position selected, this can be done by moving the floating point 94 to the position to the right of the sign = "with the button" * "16, the first vertical segment displayed in the position the

  left-hand side corresponding to D 6 then starting at

  If you wish to modify this in the memory, by going from the low level to the high level (0 to 1), pressing the increase button 26 causes this modification to be entered in an intermediate register in preparation for entering the electrically modifiable read-only memory 44 and changes the display so that the upper vertical segment of the D 6 position lights up

  while the lower vertical segment goes out.

  If you want to change one or more digits in the memory position corresponding to the selected connection, for example J 05, press the "" button to move the flashing floating point to

  the viewing table 18 to the position sou-

  for example the position of the next vertical segment

  to the right of the rightmost digit 20, corresponding to

  This position indicates a blink and since it is high, as shown in the figure, depression of the decrease button 24 causes

  the loading of this modification into the inter-

  The display shows that the memory position has been changed from high to low. If the "config" button 16 is pressed at this time, the display flashes the positions of the binary digits D 6 -DO that come from be modified, as a final check, of the appropriate modifications having been selected before pressing the "input" push button 16 to introduce the new connection configuration into the appropriate position of the modifiable read-only memory

electrically 44.

  It can also be seen in the table that the modem 12 can, through the front panel 10, be configured to perform certain particular tests and

  to check certain states inside the modem 12.

  In the positions 90-94 of read / write commands in the electrically modifiable read-only memory 44 according to the invention, are recorded 1 and 0 binaries which indicate the state of the modem speeds chosen For example, the value 100 in the bit positions D 6-D 4 for the memory position 90 may indicate that the modem speed chosen for the transmission is 4800 bits / s Also by way of example, the value 100 in the same bit digit positions for memory position 92 may indicate that the normal speed chosen for access D in a multiple access modem is 4800 bits / s The memory positions 95-97 contain

  information in binary form corresponding to cer-

  some test programs to run in the modem by its

software controller 41.

  The other buttons 16 of the front panel 10 assume various functions, in a manner similar to that described above. For example, the depression of the test buttons 16 results in the display of a test menu,

  for example, self-interrogation, auto-error, error

  end-to-end (E E) and end-to-end interrogation, which can

  be followed to select the desired test menu.

  The test function control information is recorded

  stored in memory positions TEST 1, TEST 2 and TEST 3 of the table, in a random access memory 64 that is part of

  of the microprocessor 30 of the option controller, this information

  may be written or extracted for execution

  of test programs or for the modification of

  test programs They do not go out saved in electrically readable read-only memory 44 so that the modem

  can switch to normal mode in the event of a power failure.

  tation. The "SEL UNIT" key allows the operator of the modem 12 to display a desired multi-digit code, for example for a remote modem, on the

  visualization and, by introducing this dode through the

  the "input" key, to introduce the equiva-

  three-digit digital slow, up to 255, in RAM 64, in the RDROP position This allows communication to this modem via the option controller's microprocessor 30 and the line

  Transmission, for example, to carry out a verifica-

  status, a configuration change, or

  the course of a test, then pushing the

  appropriate tones 16 of the modem 12 as if these functions were performed in the modem 12 as described in

this memoir.

  The access selection "SEL ACC" key allows the operator to select a particular access in a

  modem 12 which is multi-access and display these para-

  meters, or to modify its speed or test mode, by using, at the same time, buttons

appropriate 16 control.

  Button 16 "Loop" is for selecting and conducting a special loop type test of local modem 12 or remote modem 68 Loop test information is also stored in TEST 1, TEST 2 and TEST 3 The erase button "EFF" must be

  be depressed to remove the modem 12 from the loop test.

* The "Call" button is used to select a desired coded message and desired code corresponding to a particular remote modem 68 and to transmit

  this message to this remote modem 68 via the transmission line

  Message may be encoded, by numbers, of 1-10, 11-15, the operator in the remote location being able to recognize, from the number thus displayed on the display board 18

  remote modem, the meaning of the message.

  The erase "erase" key when depressed erases, for example, all the trial functions or the current remote modem address, and restores the modem 12 to normal operation. When a remote modem 68 is addressed via the front panel 10, the "remote" indicator 22 comes on and when tests are carried out using the modem 12 in test mode, the "test" indicator 22 lights up Otherwise, when the modem

  12 is on, the "local" LED is on.

  In the following table, the abbreviations used

  have the following meanings: F B = change

  1 (speed of modification of the operation for

  continue treatment); DL = digital loop; AND -

  error test; DT = dynamic test (interrogation); EN.ER = error counter validation; AL loops = analog line loop; MSLP = modem side loop; LSLP = line-side loop; CXR on = carrier tone present TX in = TX controller (transmission installed); MP in multiple access installed; TPE = test combination validation; MDSR = given group of main modem ready; V 54 DL = V 54 compatible digital loop; R E B = elastic buffer reception; LR E / A B = local hold validation / return response; RX Data Clamp = put on hold

  receiving data; CTS DLY = Delayed Delay

  issue; RTS con = constant RTS (request to be transmitted) EXT / INT = external or internal clock; Y 4 Pattern = simulator access function off;

  MPDSR = multiple access data group ready; NARS = community

  remote adapter network EIA = interface; SSEN = speed selection coding; SQG = good quality signal; Lock FP = front panel lock (only unlocked state); Lock St = locking connections (locked sets, except condition and test); RMC = remote modem command; TX = TX controller; MDCDON = in-run detection of the MDCDSW modem data carrier = switched data carrier detection

  modem; D P F O = digital output of power outages

  tion; SEC RTS = secondary channel transmission request; SEC CDON = detection in secondary carrier mode; SEC CDSW = secondary carrier switched detection; FSK ENA = allowed frequency shift modulation;

  FSK SW = Frequency shift modulation

  ted; D P F I = digital power failure input: ATXC Alrm = transmission access clock failure alarm A; ARXC Alarm = access reception clock failure alarm A In the 98-9 F positions of the RAM,

  EIAST 1-8 is an EIA state for access.

  These are displayed on the front panel and are also accumulated over a period of 2 seconds and coded in 8 bytes of information to be transmitted to the remote modem or the network controller. The EIA coded, EIAEN 1-8 (D 8-8 F) is written using D 8-DF in the TX controller. The 98-9 B positions memorize the high state of the access signals and the

  positions 9 C-9 F memorize the low state of the access signals.

  MTSTMD means the modem in test mode; IDCD is an internal data carrier detection; IRTS means an internal request to be transmitted; ARDL denotes a remote access EIA digital loop input A and AFB designates an access access hold A to

  from EIA (speed selection for access A).

  It goes without saying that many modifications can

  can be made to the modem described and represented without

  out of the scope of the invention For example, the configura-

  particular connections, test modes, and status checks stored in ROM or RAM as previously described are not included as examples and other variants

  can be used in the present invention.

TABLE MODEM TABLE HP TABLE TX

MT 2 MT 1 MTO PT 1 PTO TT 1 TTO

M.P ELOIGNE TREMBLEMENT GAIN XMT

  P.P CENTRAL TONE TXG 3 TXG 2 TXG 1 TXGO

EMISSION.

T 52 T 51 TSO

CTS DLY RTS CON

SAR

  MD, HP DESIGN ONLY CONNECTIONS FROM OC; READINGS AND WRITING TX '

BOARD

D 2 D 3 D 4 Di

0 R D R E

READIND, WRITING

NO

CONNECTION

D 6 D 5 N D 3 D 2 Di DO D 7

V 54 NDSR

0 DL

LOCAL cot; / - Dcâ

SEO TRAINING RX

R 52 R 51

  JOINT COMMITTEE 80

LOOP

t Anq RX RXGO

B MAINTIEN

COMPLETED

ON PRSET

J 2 MD if ci

GAIN LOOP

LPG 1 LPGO

LR.E / DATA

A.B IMPLEMENTATION

SOUFOES

HOREN GES TX ISSUED.

TXC 51 TXCSO

HORL EXT / -INT

82 C 2 33

83 C 3 J 4

84 C 4 is

WAITING

N) I "

MRTS SW TXC

SOURCE IIORL MODEM

A A Cs J 6

MD 85.

Me Ksi MCKSO '' RX TX

A A

CTS DLY RTS CON HORL EX TF I-NT

RX TX

  B B BTS DLY RTSCON 110 RL EXT / -i N-T

RX TX

D D D D

CTS DLY RTS CON

0 c C

HORL EXT / NT

RX TX

0 C C

86 C 6 J 7 '

  HP 87 C 7 is 1%) Ln r%) -r- Ili w LY

ENIS Y 4 ENTREF / OUTPUT

D C B A -

RECEPT Y 4 ENTREWSORTIE

-TP D C A A

VALIDATION DYNAMIC ACCESS

NORMAL REVERSED DATA

  Mn, HP DESIGN ONLY CONNECTIONS FROM OC 1 READINGS AND TX WRITINGS.

TABLE (continued 1)

0 R D R E

READIND, WRITING

D 4 D 3 D 2 Di DO NO

CONNECTION

  D 7 Di DS Y 4 ph "gpm 88 'Cs 39 89 C 9 alo BA CA ail P 2

MASTER

0 i

SLAVE

ORDER

(# ACCESS

M

DTR / RT

Pl MPDSR

CONANC-1

ACCESS vpl EXA NARS

ENTREëSOR'I

VARIABLE

  VPO RDL / SOG A D cB B A D C x $ SEN 8 B Ca 312 8 C, cc J 13

BLOCKING BLOCKING RMC /

0 FP ST TX

Sensor control

failure allm.

Circuit command

replies recept.

nufi 1 ('rj that

KDCDON / D-P-F-0- /

x

MDCDSW SEC RTS

SEC CDON 'RECONFIG

  x SEC C No MAL gsg x FSK Sw Sec 'cb Conoande execution reconfig.

coimidnde reqen.

  Analog Receiver Distress Direction Command Ccmret & iet?, ircuit rfense recep ana og ue

Order -

order execution

Regen Conimande

digital receptacle

8 D CD J 14

  this 315 or Crlr% 3 LA RL%) C- r%) LY W READING AND WRITING BY N P AND T X OF CONMAMDE BLT ES I ITS LOCAL SPEED TABLE (continued 2) o

READING

R D R 8

NO

WRITING CONNECTION

DO SPEED 1

Dl SPEED 2

D 2 SPEED 3

93 D 3 SPEED 4

94 D 4 SPEED 5

ODS TES Ti 1

96 D 6 TEST 2

97 D 7 TEST 3

O o o O a

RDEPS N E

SPEED MODEM SPEED T

48 24 O

ACCESS B NORMAL

48 24 12

NORMAL ACCESS

48 24 12

ACCESS B? bl

O 24 12

ACCESS O F Bl

O 24 12

REMOVE ANY CALL

TEST

LOCAL PRESENT

EN.ER ALL B O O UCLES

CTR MSL P LSLP

<L 3) <L 4>

TX Im HPIN RECYCLING Tl. D 3

REGENERATION

o o O LD n CA 3

CXR ON

TPE Tl. D 2 Dl

SPEED MODEM EX

48 24

ACCESS TO NORMAL

48 24

ACCESS C NORMAL

48 24

ACCESA F B o 24 ACCESC P B

O 24

AND DT

C B

CA 2 CAL

x x

SILENCE X

Su 1 R

OR <DRES

DO O

CLOCK

A DL, AND DT

CAD At'P Ei i

X OTHERWISE

  x f Po w- (il r% a J r 1 'J 6 m ro Cj CM Ln Ci

0 1 $% SVIU

0 LISVIS

0 9 LSVIS

  Usa usa usa g'-m Sva SVEI SVEI cxil

M VSIDDY

  IOVH has sai Dy z Sa Doi has His DDY axi. IH y Sa DDV ZQ a SSDDV 0 Sa DZ) v 9 Sa Dav 'm Sm M DU afflylm 0 Sisyzs 06 tiovia 96 0 tisvia V 6

0 E & SVIZ 66

  0 lisviz 86 The WON uniliffos gani D 57 a 'a a X O ivom vis ZY La Satiyma 1090

Q-M M-1

  p rli USCT XSCI XSCI si'd Ublo OF affl Viv K 9 has its 9 N O d a x (c have Tne) nyaiavz IDINIX ja Id Ix Y sueiolis Ja cza -The a rd OC mi M t CM u'i Cu

L 3 LY

  93 9 y yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

L ZSS-UIA

9 assuzl A -otto'ena In I ri'Noua

TMMOUS

gvilsax

TY & CDIS

  NOVIR xxxxxxx aa ND 10 qa angwo T H qs SéPray '0 Its DDY O snoi Ny R xa His DDY assall A y His DDY O SSDDY has SSDDI if 91 cool LXZ anôlwv NXA His DDY 0 ZU 3 ZEUS My silent 9 ZU $ 3 SNOIIVOOUHZINI NO has aug / una UH 3 has helped WOD Sa 'q'S'N olus T Tua ZTMS utes My STUZ I ivoouuaimia unsuuaknauusea Nawo D its so oos TOS zos UOS gay az Illyno MONTH Tiu ZIDI MMO Miq fl Va AIN DOSN

SMIDY SSDDV

  WHERE TU ta ta YU 4 u ozamma 42 & VU a a zun & Dzlz his Bal M voum O

SPECIAL DEMANDS

TABLE (continued 5) 0 R

READING

AS A 9 X AB AC AD D R E

WRITING NAME

Apreo

D 7 D 6 D 5 N D 3 D 2

SPECIAL DEMANDS

ORDER ANALOG PARAMETXES

  ACCUE RECEIPT REQUEST ADDRESS T 7

Dl DO

ú 9 T 7 ADDR

SYNCMO

NORZO n SPEED SYNC

NO RE-PONSE AVAILABLE

He,:, BC

COPTINUATION

SERNOR

D 044 r ES S UnidNTES

  ACKNOWLEDGMENT RECEIPT REQUEST N ° OF SERIES

DONNL-4 S EXISES FROM MP

TXO COGBIT COGEN TXI As AP

TXDATA

TXDTAR

  TX 2 x x rla LM r ') rla LM tw M PO Cj -t (1-J Ln CI-J The sa tu tu te z XCRIO MON

IJVNI S

  atwac-qu 1 clam 1 j'IV aeu 3 sax ahuas "IDYZ-Idbi Our asmodax

T O T

T O T

T O T

T O T

T O T

T O T

T O T

0 - T T T T T oa T T L-

T O

* 1 O

0 O

the ta

0 'L

0 the

0 T

  úci ipa (9 9,4, rne) nvaiavi (I Nssaud Y 1,% = Wrlnag Snnglnodgl G 9 t) SZ 7 n D Zd S 035 N Od ZU Po clj -Y (% j Ln Cj do 3 a to Da " G VU 6 has his auniilaiz sunioai a Id has he O e Nayxa LN 3 yxa

983 YZ 3

  smavis t Navis E Naviz z Naviz Titzyza NO rua O 53 DOY

ZN 3 13 SRDDY

  lxl Dv oxkt osci Taa usci Sa Dov amm Go U aa OD y SEIDDY T Na CI Tua O Tua O lau axis situ LIR x mm 3 ao D Sa DDV zci úG ta LU (L nvaiavz Ra aimxva y) to m & lzwsmmm y Ta xx 03 m axu Co (M & S SZZCIOD 9,30 DYOCI SMENNOCI aunj 11 ID 2 l

  XIA SIG AND ZIA ORDER BETWEEN OC AND HP.

0 R D R E

READING WRITE NO D 7

Bo RIASIO TABLE (continued 8)

DS N

mse 14 TSTHD D 3 D 2 Dl

ACTIVE ACCESS

D C B

DO to D 6 KDSR r 1 j RDL c

SELECT EIA SPEED

  D c Da Bb ACHO 9 rj (il r 1 j rlo Lq L 4 B - n M Po Cj -It Cj Lrb Cu

0 83

0 t D

0 OD

0 From

0 89

0> 9

  0 or (Hivawi) 0 xxavàzi JL 1 (Elyd) 0 xxavtlu 2 LQL NOT 'sufil Dali 3 anlilamw ssvffd sa uaxlii c asvila aa, 3 D Nanbaud an NOIIVISNVUJI solubilis invs auqalifflouvi anagus siviovu unauus unasllv D 3 unasan D aul YN 19 vmi M 'nozd Unasiliv Da unasan D' lm soemau Ci Here Zn M ta se 9 ci ZSN Od RU (6 Oq Tns) rvaiteii, IDIN y mm to xiluyd Y xi, szai qwma On sanolwmâv saumswaya MODEM CONTROLLER BMUT V Effl DATA RECEPT M p. TABLE (continued 10)

IREPONSE (RDATA FORMAT)

D 7 D 6 DS D 4 D 3

D 2 Dl DO RXO ORDER

ENTRANCE

DATA

RX EO-Fr name

RXDATA

1 RCOG

0 RX 2

Rxl r \) Ln rl%) 4.- rl%) w Lj

Claims (10)

  1 Modem, characterized in that it comprises a device (10) intended to apply inputs to this modem (12), a fixed memory (46) intended to record information corresponding to one, selected, of several   possible configurations of the modem, a   changeable memory (44) for storing information corresponding to a plurality of selected modem configurations, a device (30) responsive to an input from the input device, loading the selected content of the fixed memory into the modifiable memory, and a device (30) located inside the modem for configuring the modem according to the information contained in the changeable memory.   2 modem according to claim 1, characterized in that it comprises a device (30) which, in response to an input of the input device, selectively load information corresponding to a chosen configuration   modem in the editable memory.   3 Modem, characterized in that it comprises a device (10) intended to apply inputs to the modem (12), a modifiable memory (44) intended to record information corresponding to one, chosen, of several possible selected configurations of the modem, a device (30) which, in response to an input from the input device, selectively loads into the modifiable memory information corresponding to one, selected, of a plurality of possible modem configurations, and a device ( 30) located inside the modem and intended to configure the latter according to the information contained in the changeable memory.   4 modem according to claim 3, characterized in that it further comprises a fixed memory (46) for recording information corresponding to one, chosen, of several possible configurations of the modem,   and a device (30) which, in response to an input from   the input signal, load the contents of the memory fixed in the editable memory.   Modem according to one of Claims 2 and 3,   characterized in that it further comprises a transmission line (32) connecting the modem to another modem on that line, the device for selectively loading information corresponding to one, selected, of a plurality of possible selected modem configurations. in the modifiable memory also responsive to receiving a predetermined signal from the other modem via the transmission line.   6 modem according to one of claims 1 and 4,   characterized in that it further comprises a transmission line (32) connecting the modem to another modem located on this transmission line, the device for loading the contents of the fixed memory into the modifiable memory also responsive to the reception a predetermined signal from the other modem through the transmission line.   Modem according to any one of the claims   1, 4 and 6, characterized in that the fixed memory is   gured to record information in tables   each table corresponding to one, different and prede-   terminated, of several possible modem configurations, the device for loading the contents of a fixed memory into the modifiable memory comprising   means of selecting from the different tables   those to be loaded into the modified memory. reliable.   8 modem according to one of claims 5 and 6,   characterized in that it further comprises a device   (18) for controlling the state of operating parameters   another modem on the transmission line.   9 modem according to claim 8, characterized in that it further comprises a device (16) for triggering the test of another modem on the line of transmission.   Modem according to Claim 1, characterized   in that it further comprises a visualization device (18)   for displaying information stored in the first memory or in the modifiable memory, which comprises several digits (20) consisting of segments   horizontals and upper and lower vertical segments   and means for illuminating upper or lower vertical segments of adjacent digits to display an indication of a respectively high state   or down presented by each bit of a byte of memory.   11 modem according to claim 3, characterized in that it comprises a display device (18) for displaying information stored in the modifiable memory and which comprises several digits (20) consisting of horizontal segments and upper and lower vertical segments means for illuminating upper or lower vertical segments of adjacent digits to display an indication of a high or low state, respectively, presented by each bits of a byte of memory.   Method for connecting a modem (12) to a selected configuration thereof, characterized in that it consists in recording in a memory (44) that can be read information corresponding to one of several possible selected configurations of the modem, and electrically extracting the information from the memory and transmitting it to a circuit (30) placed inside the modem to give the modem a configuration   corresponding to the recorded information.