FR2571164A1 - CONFIGURATION MODULE FOR AVIONIC SIGNAL PROCESSING UNITS. - Google Patents

Abstract

THE PRESENT INVENTION RELATES TO A CONFIGURATION MODULE FOR AVIONICS SIGNAL PROCESSING UNITS. THE INVENTION PROVIDES AN APPARATUS AND A METHOD FOR REDUCING THE NUMBER OF ELECTRICAL CONNECTIONS REQUIRED TO DETERMINE THE DISTANCE, THE OPERATIONAL CONFIGURATION OF A SIGNAL PROCESSING UNIT OF AN AVIONICS SYSTEM AS A FUNCTION OF OPTIONAL SETS OF SIGNALS OF ENTRY AND EXIT. THE REDUCTION OF THE NUMBER OF CONNECTIONS IS ACHIEVED BY USING A CONFIGURATION MEMORY32 THAT IS MOUNTED ON A DRAWER THAT RECEIVES THE ENCLOSURE34 CONTAINING THE SIGNAL PROCESSING UNIT12. THE NUMERICALLY REPRESENTATIVE CODED SIGNALS OF THE SELECTED OPTIONAL INPUT AND OUTPUT SIGNALS ARE STORED IN A PERMANENT PROGRAMMABLE MEMORY32 OF A CONFIGURATION MODULE30 WHEN SIGNAL PROCESSING UNIT12 IS INITIALLY INSTALLED IN THE AVIONICS SYSTEM. APPLICATION IN PARTICULAR TO FLIGHT MANAGEMENT COMPUTERS.

Description

In general, the present invention relates to methods and

  apparatus for adapting a signal processing apparatus to operate with

  input and output devices of various types and configurations

  rations. Although the present invention finds applications

  in various types of electrical and electronic systems.

  In its preferred form, it is particularly adapted for adapting a signal processing unit of an avionics system to operate with signal sources and signal matching devices that can

  also be used in this particular avionics system.

  ticular. Advances in digital signal processing techniques have been made possible to realize a wide range of electrical and electronic apparatus using a programmed digital signal processing unit in combination with various types of sources

  signals and signal use devices.

  In some of these systems, it is necessary that the programmed digital signal processing unit is capable of operating in connection with other signal sources and / or other signal utilities that exhibit signal characteristics. variety. This requirement may exist for many reasons, including system user preferences, or to facilitate the use of existing signal sources and usage devices that serve as components for another electrical or electronic system that is installed in the system. same location or in the same system. In case a significant number

  various signal sources or devices for use

  the signal provided by these signal sources and / or a disparity between the signals required by the signal signal processing to work with the various components

can be serious.

  The problem of processing various signal sources and signal usage devices has become particularly troublesome in relation to the units

  signal processing which are used in the systems.

  avionics of the type used in commercial aviation.

  In this regard, the air carrier or the company managing the aircraft generally determines which types of avionics systems may be installed on the various aircraft in the carrier's fleet, and further specifies the configuration of each system,

  including which particular signal sources and

  Signal usage must be used. Without considering whether a particular use device is a cockpit display unit, an actuating means, or another avionics system, -more than one

  alternatives are often presented to the carrier.

  In many cases, there is a significant disparity

  between the nature and characteristics of the excitation signals

  required by the various possible use devices. In addition, modern transport aircraft include many avionics systems and often,

  the excitation signal required by a user device

  chosen may come from various sets of signals

  input. Such functional units of

  They include signals provided by other avionics systems and signals provided by various possible transducers, detectors, and actuators. In addition, in addition to the input signals required to provide the output signals to the systems, some processors

  avionics system signal require informa-

  inputs that modify or control how the signal processor works. A wide variety

  this type of signal information may be necessary.

  For example, it may be necessary to provide the process

  a signal representing the identification of the aircraft (ie "tail number") in cases where the proper

  signal depends on the aircraft or particular type of aircraft.

  In some cases, even the language in which a system displays messages for the crew or passengers of the aircraft can be controlled by providing a signal

  chosen particular to the signal processor of the system.

  For all these reasons, there is often a disparity

  noticeable difference between the nature and characteristics of the

  input signals that are provided to the processing unit

  signal from an avionics system.

  To facilitate the satisfaction of needs

  and the desires of various air carriers, manufacturers

  equipment and avionics systems - have generally attempted to

  signal processing of various avionics systems.

  in order to provide easily selectable options

  adapting a particular avionics system to a confi-

  specified guration. In general, these configuration options are made available by arranging the signal processing unit to be able to provide each type of possible output signal and to be able to operate with each input signal. possible. In these arrangements, a selection

  of the desired configuration is carried out

  optional connection of various circuits and terminals that are contained in the signal processing unit. More particularly, the signal processing unit comprises

  often several terminals that are electrically intercon-

  connected to the circuit of the signal processing unit, so that the interconnection of the various terminals and / or the connection of the various terminals to a particular electrical potential -4 (for example the low or other specified voltage) signal processing unit the desired configuration. Indeed, in such an arrangement, the signal processing unit is "informed" of how the avionics system is designed and is adapted to operate with the input and output signals that

  are associated with this particular configuration.

  In prior art arrangements, the interconnections that define the desired pattern have been established in various ways. For example,

  in certain arrangements of the prior art, a plurali-

  Switches that determine the operational characteristics of the signal processing unit or are provided in the signal processing unit or are mounted in the enclosure that contains the signal processing unit. In this type of arrangement, the switches are arranged to provide the desired configuration before the signal processing unit

installed in the aircraft.

  This particular approach of the prior art has at least one disadvantage. In particular, the signal processing units of avionics systems are generally housed in a sliding cabinet

  in a drawer that is mounted in electronic cabinets

  c. Electrical adaptation connectors that are mounted on the drawer and the signal processing unit

  allow quick removal for maintenance, repair and

  tion or replacement. Since many transpor-

  operators operate various types of aircraft and often provide a particular type of configuration of different avionics systems for the various types of aircraft, airline personnel must position the switches of the signal processing unit to provide unit configuration appropriate for this particular aircraft type and shall test the signal processing unit for its proper operation prior to

  installation. This can lead to delays which

  the maximum use of the airplane and

  disrupts departure and arrival times.

  In a second approach of the prior art, which overcomes the aforementioned difficulties of replacement,

  each terminal of the signal processing unit which determines

  mine the operating configuration is connected to a pin (or receptacle) of the unit connector

  signal processing. In this arrangement, the configuration

  operation of the signal processing unit

  is established by electrically interconnecting the receptacles

  adapted keys (or pins) of the connector that are mounted

  on the drawer that receives the signal processing unit.

  Although this particular approach of the prior art allows the wiring of the aircraft to define the configuration of the signal processing unit, the number of configuration options to be processed has increased to such a point that this technique is at least partly undesirable. In this respect, the availability of additional avionics systems and components that produce other input signals and require additional output signals has reached the point where it may be necessary for a signal processing unit to

  particular, provide a large number of options for

  configuration. This means that a large number of electrical connections must be made at the connector which adapts with the signal processing unit. Thus, a large number of connector pins must be provided to determine the operational configuration of the signal processing unit. This means that connectors

  relatively large ones should be used and a quantity

  A greater effort is required to install the jumpers or connectors that determine the configuration of the signal processing unit. The result is

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  colt, complexity and weight. -

  According to the present invention, the operating configuration of an avionics system signal processing unit is established by a memory unit which is contained in a bot configuration module.

  separate tier. Digitally encoded signals which characterize

  The desired configuration is stored in the memory unit or before the initial installation of a signal processing unit or the instant when the signal processing unit is installed in the avionics system. Preferably, signal codes which define each configuration variable (e.g.

  the type of signal sources and devices used

  the signal used by the system and various other system parameters) are stored in the memory unit in a predetermined sequence. Whenever the signal processing unit is replaced, the codes are supplied to the signal processing unit

  newly installed as a digital signal.

  Thus, the electrical connectors of adaptation which inter-

  electrically connect the signal processing unit with the other components of the avionics system should simply include a small number of connections that are provided to give a configuration to the unit

signal processing.

  In the currently preferred embodiments, in which the signal processing unit uses a programmed digital signal processor, the configuration module includes a serial access programmable random access memory unit and is mounted on

  the drawer that receives the signal processing unit.

  In this arrangement, only six electrical connections are required between the signal processing unit

and the configuration module.

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  In an implementation of the presently preferred embodiment of the invention, the avionics system comprises a control and display unit which is mounted in the cockpit to facilitate entry by a keypad of data and information. various system controls and to facilitate display on a radius tube

  cathodic information and system instructions.

  In this arrangement, the signal processing unit is programmed to produce a system installation procedure in which the control and display unit is used for storing the configuration codes.

  in the memory of the configuration unit during the

  initial setup of a signal processing unit.

  Furthermore, in systems that use a programmed digital signal processing unit, a signal that is identical to the signal stored in the configuration module is read from the permanent memory of the signal processing unit during the installation procedure. initial. This information is compared with the signal stored in the configuration module each time the avionic system is activated ("power on"), to verify that the configuration of the signal processing unit is correct and to ensure that 'no change has occurred in the signals

  stored in the memory unit of the configuration module.

  tion. In addition, the memory configuration information

  in the permanent memory of the signal processing unit serve as a backup copy of the appropriate configuration data in the event of a failure.

  or removal of the configuration module.

  These and other aspects and advantages of the present invention will become apparent upon reading

  the following detailed description of an embodiment

  given by way of example, taken in conjunction with the accompanying drawings in which: - Figure 1 is a block diagram showing an avionics system in which the operational configuration of the processing unit

  of the system is established in accordance with this

  tion; FIG. 2 is a perspective view of a signal processing unit and the mounting drawer which receives the signal processing unit, this view showing a configuration module mounted on the mounting drawer and electrically interconnected with

  the signal processing unit according to the present invention.

  tion; and FIG. 3 is a flowchart illustrating the installation procedure of the embodiment of

  the present invention shown in FIG.

  As shown in FIG. 1, an avionics system of the type to which the present invention essentially refers comprises a programmed digital signal processing unit 12 which is connected to a plurality of signal sources 14 and is connected to a plurality of signal sources.

  of signal use devices 16. In operation

  a central processing unit CPU 18 of the unit

  programmed digital signal processing 12 sample

  sequentially outputs the input signals provided by the signal sources 14, processes the received signals and

  provides output signals to the user devices

  In the arrangement shown in FIG. 1, each signal source 14 provides data to the CPU 18 through a data input port 20 which is connected to the CPU 18 via an address and data bus 22. Similarly, the output signals provided by the CPU 18 are selectively coupled to each of the various signal utilization devices 16 via the data bus 22 and a data access.

associated data output 24.

  As known to those skilled in the art, the described arrangement of the digital signal processing unit 12, input signal sources 14 and signal utilization devices 16 is typical of a variety of avionics systems of the type using a

  Signal processing. Such avionics systems include

  for example, navigation systems of various

  types and descriptions, various types of communication systems,

  various types of flight data recording systems and various types of operational monitoring systems. As will be appreciated by those skilled in the art, the configuration and nature of the signal sources 14 and signal utilization devices 16 of Figure 1 depends on the particular type of avionics systems involved. For example, signal sources 14 may be various conventional transducers or may be

  other avionics systems that are used on the

  using the relevant avionics system. In a way

  analogous, the signal utilization devices represent

  Fig. 1 may be conventional indicators that display crew information or may be other avionics systems that require a signal provided by the relevant avionics system. In addition, those skilled in the art will appreciate that the avionics systems schematized in the blocks of FIG.

  include components not shown in Figure 1.

  For example, such devices may include an apparatus such as signal acquisition units, digital-to-analog signal converters, and

  other apparatus which actually receive or

  process the signals used in this particular avionics system. Regardless of the type of avionics system and the particular signal input and output arrangement, those skilled in the art will appreciate that the CPU 18 of the digital signal processing unit 12 includes an arithmetic unit and logic that is interconnected to a random access memory (RAM) and a read-only memory

  (ROM), none of which are shown in Figure 1.

  The CPU is programmed by instructions stored in the ROM to sequentially access the data provided by the signal sources 14, process the signal data in connection with the instructions stored in the ROM, and provide device output signals. using signal 16 in accordance with additional instructions stored in the ROM. During these operating steps, the R4M is used for temporary storage of calculation data and to perform various register functions that are required for proper sequencing of the data.

CPU 18.

  As shown in Figure 1, some avionics systems include a control and display unit. CDU 26 which serves as an interface between a member of the flight crew and the digital signal processing unit 12. Although various arrangements are possible, the control and display unit of Figure 1 comprises a keyboard 25 (which allows data to be transmitted to the digital signal processing unit 12) and

  includes a cathode ray tube (or equivalent display

  slow) 27 (which allows the display of various information).

  As also shown in FIG. 1, such a control and display unit can be coupled to the bus 22 by means of an allocated data port (called CDU access 28 in FIG. 1). In addition, in many cases, the digital signal processing unit 12 of an avionics system includes a power supply 31 for supplying electrical power to the CPU 18 and to various other active circuits contained in the communication unit. treatment

signal 12.

? 1 16 4

1 1 116

  As previously mentioned, various types of signal sources 14 and signal unit utilization devices 16 are used to realize various types of avionics systems. In addition, various signal sources and devices for use

  are often available for a particular type of

  link avionics systems. Thus, even though the relevant avionics system may be a particular type of navigation system that provides certain information to the crew, the signal usage devices may include several different types of indicators and / or navigation information. provided by the particular navigation system may be provided to other avionics systems. Similarly, it may be possible to provide the required navigation information from various signal sources, including signals provided by various other avionics systems.

  and / or signals provided by various variants of

  ductors and detectors. For example, the described invention

  and claimed here is commonly used in a calcula-

  flight management system which provides many features

  classic navigation features and which in addition provides

  additional useful navigation information.

  This flight computer comprises a large number of serial data ports which functionally correspond to the data ports 20, 24 and 28 of FIG. 1, these data ports being of various types including ARINC 429 data accesses, data accesses and data ports. RS 422 serial data access and serial data access using other

  particular prototypes. Although the nature and characteristics

  the signals emitted or received by a large number of

  data access are identical in each installation.

  the flight management computer, options must be provided for a certain number of data

  in order to adapt to the various devices

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  and optional signal sources. In this case, in the production of a current flight management computer according to the invention, four entry ports are

  available to provide position signals of the

  to the flight management computer, three optional signal sources being available for each of these three ports. In addition, eight radio frequency tuned accesses are provided to receive various other signal information, and various fuel flow rate signals may be provided for

  any or all of the four fuel flow accesses

  rant. In addition, there are many data ports in which an option exists with respect to the

  connection to one of two signal sources or

use of signal.

  According to the present invention, the configuration of the digital signal processing unit 12 to operate with the various possible sets of signal sources and devices for use

  of signal and processed by a configuration module 30.

  As shown in Figure 1, the configuration module

  ration 30 includes a configuration memory 32 which is interconnected with a programmable data port 34 of the signal processing unit 12. In operation, the CPU 18 of the digital signal processing unit

  12 is programmed to process each of the option-

  of signal sources and devices for use

  of signal. A digital signal that represents the configuration

  desired source (eg sources of other signals and

  selected use) is stored in the configuration memory 32 or before or at the time of installation of the system. Whenever the avionics system is then activated, the CPU 18 accesses the

  data stored in the configuration memory 32.

  This information is used to give a configura-

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  to the digital signal processing unit 12 so that the CPU 18 selectively performs appropriate signal processing to the signal sources and devices

  signal usage used by the avionics system.

  According to the present invention, and as indicated in FIGS. 1 and 2, the treatment unit

  of digital signal 12 and the configuration memory unit

  32 are encapsulated and mounted separately. More particularly, in the arrangement of FIG. 2, the digital signal processing unit 12 is contained in a conventional avionics enclosure 34 which slides in a drawer 36. In most installations, the drawer 36 is mounted in a panel (not shown in Figure 2) that receives the various other electrical and electronic equipment carried by the device. Regardless

  the way the drawer 36 is mounted, the configuration module

  30 of the arrangement shown is mounted on the upper surface of a support assembly 38 which extends upwardly from the back of the drawer

  36. When the avionics enclosure 34 is pulled to the rear

  re in the panel 36, a connector 40 (which is mounted

  on the front of the support 38) engages with a connection

  adapted to the avionics enclosure (not shown in Figure 2). The electrical connections provided by the collector 40 and the adapted connector of the avionics enclosure 34 provide the electrical connection between the digital signal processing unit 12 and the configuration memory unit 32, the signal sources 14, the signal use devices 16 and the unit

control and display 26.

  As shown in Figure 1,

  latively few electrical connections are needed

  between the configuration memory 32 and the processing unit

  12, although many options are specified by the data stored in

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  the configuration memory 32. For example, the configuration module 30 which is used in connection with the previously mentioned flight management computer uses a serial programmable permanent memory of the NMC9306 / COP 494 type available from the National Semiconductor Company. Corporation of Santa Clara, California, as a configuration memory 32. In this embodiment of the invention, only six electrical connections are required between the configuration module 30 and the digital signal processing unit 12. As indicated In Fig. 1, two of the required connections couple the operating potential (Vcc and system ground) from dc of the power source 31 of the digital signal processing unit 12 to the configuration module 30. Two of the required connections remaining electrical connections serve as input and output data connections to the configuration memory 32. clock are coupled from the signal processing unit 12 to the configuration memory 32 via

  one of the remaining electrical connections and the last one

  The electrical connection is used in connection with the clock and data input connections to select and control the operation of the configuration memory 32 (i.e. write data to memory, read data from memory or

  deleting a specified portion of the memory).

  The structure and operation of the invention

  This will be better understood in connection with the procedure used in the commonly used embodiments of the invention with respect to the initial establishment of the operational configuration of the processing unit.

  12. In this respect, in the calculation of

  The above-mentioned flight management manager who uses the invention, an example of a user device that is subject to various alternatives or options is the horizontal situation indicator system. As is known from the avionics technique, an indicator

  horizontal situation displays information that includes

  heading and bearing of the aircraft. As is also known in this art, several types

  possible horizontal situation indicators exist.

  There are also various options for how the horizontal situation indicator displays heading and bearing information and alternatives for the type of signals that control

  bearing and road movements.

  The way the embodiment

  presently preferred embodiment of the invention establishes the

  of the digital signal processing unit for

  operation with a horizontal situation indicator

  The particular step is shown in FIG. 3. As indicated in block 40 of FIG. 3, the first step of the procedure is to determine the reference for the road exit. To facilitate this determination and all the other configuration specifications, the i8 CPU of the aforementioned flight management computer is programmed to display "prompt" on the cathode ray tube 27 of the control and display unit 26, This requires the installer to request a required configuration specification. Relative to the route exit reference specification, the flight management computer displays the message "THE ISH ROUTE EXIT IS RELATED TO: []" on the top of the cathode ray tube 27 and displays

  "1 Road" and "2 North" directly below this message.

  To specify the route reference, the installer presses the numeric key of the corresponding keypad 25 or "North" or "Route" and then presses the "ENTER" key. As indicated by the block

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  42 in FIG. 3, the CPU 18 is programmed to then display a message on the cathode ray tube 27 which requires the installer to specify whether a resolution signal or synchronization signal is used in the system to control the motion indicating the route the horizontal situation indicator system. When the installer has pressed the appropriate key on the keypad and then pressed the ENTER key, the system proceeds to the configuration determination indicated at block 44 of Figure 3. At this time, the system displays a message on the tube. with cathode ray 27 requiérant

  that the installer specifies whether the recovery information

  displayed on the horizontal situation indicator (ISH) used in the system is relative to the "road"

  of the device, or is relative to the "North". When the information

  appropriate measures have been introduced in the indi-

  previously, the CPU 18 proceeds to the step indicated by block 46, causing the CRT 27 to display a message requesting that the installer indicate whether the route signal displayed on the horizontal situation indicator is shifted by 0 (no offset) or is offset by 180. After entering the appropriate configuration specification, the CPU 18 brings the spoke tube

  cathode 27 to display a message requesting that the

  Tallator introduces the type of bearing to be displayed by the horizontal situation indicator. During this step, which is indicated at block 48 of Figure 3, the installer specifies whether the bearing to be displayed on the horizontal status indicator

  to: (1) a chosen waypoint (eg a location

  specified transmitter of a particular navigation aid or geographical location that is introduced by its length and latitude); (2) the earth path of the device; or (3) a desired heading for the apparatus. During the final step of the specification of the horizontal situation indicator configuration that is indicated by block 50 in Figure 3, CPU 18

  causes the cathode ray tube 27 to require the introduction

  the type of signal that will excite the horizontal situation indicator

  recovery information. When the installer introduces

  an appropriate response (for example synchro or

  resolution), the CPU 18 proceeds to the next required configuration determination (indicated at

of block 52 of Figure 3).

  As will be appreciated by those skilled in the art, the specifications

  configuration cations for each signal source

  and signal usage device can be determined

  in the manner shown in Figure 3 and described above.

  ously. In some cases, a determination of

  tion will require a series of steps such as those shown in Figure 3. In other

  In this case, a single specification step will provide information

  configuration requirements. For example, in the previously mentioned flight management computer that uses the present invention, the selection of the actual velocity input signal source relative to the wind is

  made by a single application in which the installation

  the system presses one of the seven indicated keys on the keypad 25 to indicate

  true wind speed is not used in this configuration.

  particular ration or to indicate which of the six optional true speed entry signals with respect to the wind

  must be provided to the system's digital processor.

  As indicated by block 54 of FIG. 3, when the installer has specified all the configuration information necessary to implement a new installation or to change a

* Existing installation, a binary signal code representing

  the optional configuration of the treatment unit.

  12 is written into the configuration memory 32 of the configuration module 30. In the presently preferred embodiments of the present invention, such as the management computer

  previously described, the CPU 18 of the Uni-

  Digital signal processing unit 12 causes the cathode ray tube 27 to display a message requesting that the installer press a first key (for example "1") if the configuration data do not have to be entered in the configuration memory. or to press a specified second key (for example "2") if the

  data can be entered in the configuration memory.

  When the configuration data is to be entered in the configuration module 30, the CPU 18 erases the appropriate memory registers from the configuration memory 32 and supplies the configuration data as a signal.

in series form.

  For example, programmable permanent memory

  NMC 9306 / COP 494 which is used in

  Current embodiments of the invention are organized to store data in 16 registers each of which contains 16 bits. To write the configuration code into one or more registers of this memory, the CPU 18 proceeds to supply the memory with the operational codes that cause the configuration memory 32 to erase the appropriate memory registers and bring the configuration data (which is stored in memory

  random access of the CPU 18 during the steps of specifying

  cation of the configuration) to be sequentially

  in the registers of the configuration memory

  32. Once the configuration data has been entered,

  in the configuration memory 32, these data are read by the digital signal processing unit

  12 whenever the avionics system is activated.

  Thus, when the digital signal processing unit 12 is replaced for normal maintenance or because of a suspected malfunction, suitable configuration data is provided to the newly installed signal processing unit 12 without

  other action by maintenance personnel.

  Although the memory configuration 32 of the presently preferred embodiments of the invention is organized as 16 16-bit registers, it should be noted that, in the preferred embodiments of the invention, the configuration data is organized into as a single instruction coded in binary having a predetermined format. Thus, the configuration data is organized as an ordered set of signals

  encoded in binary in which the selected configuration

  each signal source 14 and each signal utilization device 16 is specified by a group of binary coded signals. For example, in the embodiment of the invention that is used in the aforementioned flight management computer,

  the specification of the configuration data of the indica-

  horizontal situation consists of a group of 7 binary bits. To functionally associate the various specified parameters, this group of 7 bits is subdivided into three characters of 2 bits and 1 character of 1 bit. In the particular organization used, the character of a bit is the least significant bit of the 7-bit code of the horizontal status indicator and indicates whether the road exit is relative to the road

  from the aircraft or north. The 2-bit character constituting

  kills the next two least significant bits of the code indicates whether the raising signal of the horizontal situation indicator is: (1) relative to the route of the apparatus with an offset of 180; (2) relative to the North with a shift of 180; (3) relative to the route of the apparatus with an offset of 0; or (4) and relative to North with an offset of 0. The character defined by

  the next two insignificant bits indicate whether the

  The removal of the apparatus relates to: (1) a waypoint; (2) the path from the ground of the apparatus; or (3) a desired course. The final character (that is to say

  the two most significant bits of the code of the indica-

  horizontal position indicator) indicates whether: (1) a resolver signal is used for the route and heading signals; (2) a synchronization signal is used for the route of the aircraft and a resolver signal for the heading; (3) a resolver signal is used

  for the route of the device and a synchronizing signal

  is used for heading; or (4) a sync signal

  is used for both the course and the route

of the device.

  Those skilled in the art will note that organizing

  the configuration data as described above

  rather than arranging the signal into a plurality of data having the same bit lengths, reduces the amount of memory required to store the configuration data. In addition, those skilled in the art will appreciate that various other data compression techniques may be used to further reduce the required amount

of memory.

  In addition to the above-mentioned aspects and features of the invention, in presently preferred embodiments, the digital signal processing unit 12 has a configuration and arrangement

  periodically check the configuration data.

  In this respect, and as previously mentioned, the CPU 18 sequentially operates the digital signal processing unit 12 so that it can be accessed.

  configuration data whenever a

  This is applied to the avionics system (ie the system is "powered"). In the calculator of

  previously mentioned flight management using the inven-

  The CPU 18 includes a permanent random access memory and the CPU 18 writes the configuration data to a predetermined part of that memory each time the configuration data is written into the configuration memory 32 (for example a

  initial installation or modification of the system).

  When the configuration data is then accessed during each system power sequence, the data stored in the random access memory of the CPU 18 is compared with the data provided by the configuration memory 32. In addition, in the embodiments Currently preferred embodiments of the invention, conventional error detection (such as checks of sum, parity or Hamming code) is performed with respect to both sets of data. If the two sets of data are identical and no error is detected on either set

  data, the system power sequence continues.

  On the other hand, if abnormalities are detected, a warning signal is provided (for example on the control and display unit 26 of FIG. 1). This provides a quick detection of a malfunction in

  the configuration memory 32 or in the processing unit

digital signal 12.

  Those skilled in the art will appreciate that the embodiments of the invention set forth herein are not solely

  only as examples and that various alternatives and modifications

  tions can be made without departing from the scope and spirit of the invention. For example, although the invention has been described in relation to the digital signal processing unit, it will be appreciated that the invention may be implemented with analog signal processors by providing a specific digital circuit for determining a signal. digitally encoded and store this signal in the configuration memory 32. In addition, although the input signal sources described in connection with the exemplary embodiment of the invention are detectors and transducers The present invention can apply to two types of signals and input information. For example, the present invention is well adapted to provide signals and input codes such as the previously mentioned identification of the apparatus

  and other information that can control the characteristics

  operating characteristics of the treatment unit

particular signal.

Claims (6)

  An avionics system, characterized in that it comprises: programmed signal processing means (12) for processing one or more input signals and producing one or more output signals, the programmed signal processing means comprising means for treating   digitally encoded signals and memory means   digitally encoded signals a set of signal devices comprising   one or more sources (14) of electrically connected signal   using programmed signal processing to provide the input signals to the processing means   programmed signal, and one or more devices (16) for   connected signal receiving means for receiving the output signals provided by the programmed signal processing means, at least one of the signal devices being selected from the set of various signal sources and various signal utilization devices from among the various signal sources from the set of various   signal sources do not all have   identical signal ticks and the signals required by the various devices of use are not all identical; and   configuration memory means (32) for -   adapting the programmed signal processing means to a particular system configuration which comprises at least one selected signal device, falsant part of the set of signal devices formed by the various signal sources and the various signal usage devices , the configuration memory means being external   by means of programmed signal processing and being electrically   interconnected with it.   2. Avionics device according to the claim   1, characterized in that the programmed signal processing means is mounted in an enclosure (34) comprising at least one electrical connector which comprises connections   to provide the input signal (s) by means of   programmed signal and connections for providing the output signal (s), the avionics system further comprising a mounting drawer (36) for receiving said enclosure, said mounting drawer including a connector (40) for receiving said connector from the enclosure, the configuration memory means being mounted on the mounting drawer and electrically connectable to said driver of the mounting drawer.   3. Avionics system according to the claim   2, characterized in that said configuration memory means   ration includes a programmable permanent memory.   4. Avionics device according to the claim   3, characterized in that the permanent memory means   programmable to a configuration and arrangement adapted to provide a stored digital signal, which stored digital signal is representative of said devices selected signal.   The avionics system according to claim 4, characterized in that the programmable permanent memory further has a configuration and arrangement adapted to store a signal provided in a serial digital format, and that the programmed signal processing means has a configuration and arrangement adapted to provide said numerically encoded serial format signal to the programmable permanent memory, when the programmed signal processing means is initially installed in the drawer.   The avionics system according to claim 1, characterized in that the programmed signal processing means further comprises permanent memory means for storing a coded signal numerically identical to the digitally encoded signal which is stored in the programmable permanent memory of the means. of configuration memory, the digitally encoded signal being stored in the permanent memory means of the programmed signal processing means when the signal processing means stores the digitally encoded signal in the memory   programmable permanent means of configurable memory   the programmed signal processing means further having a configuration and arrangement adapted to compare the digitally encoded signal stored in the permanent memory means of the processing means;   programmed signal with the numerically coded signal   stored in the programmable permanent memory of the configuration memory means, whenever the power supply   Actuation is provided to the avionics system.