FUNCTIONAL INTERFACES - DESCRIPTION AND OPERATION

** ON A/C NOT FOR ALL

1. General

ECU Interfaces - General Arrangement ** ON A/C NOT FOR ALL

The FADEC unit interfaces with the following aircraft functional elements:

Air data computer which transmits air data signals to the engine control system.
Engine interface unit which : concentrates airframe signals and transmits them to the FADEC, receives information from engine and dispatches them to other systems.
Cockpit system display which provides engine parameters indication to the crew.
Throttle control system which translates the crew commands for engine power level into a command signal to the FADEC.
The thrust reverser system.
The CFDS interface which records engine data for maintenance purposes.
Electrical power supply to power FADEC while engines are not running, and to ignition boxes.

** ON A/C NOT FOR ALL

2. System Description

A. FADEC Inputs/Outputs

ECU Interfaces - General Arrangement ** ON A/C NOT FOR ALL

Engine Fuel and Control Functional Interfaces ** ON A/C NOT FOR ALL

(1) Digital Input
Inputs of each channel are isolated in order to prevent failure propagation between channel A and B and/or between both engines.
Each channel of the ECU has input ports for both ADIRU and EIU plus an input port for a spare.
The ECU checks for fault in the aircraft data links as follows.
The ECU checks each of the ADIRU 1,2 and EIU input parameters for an odd parity, a valid update rate, Source Destination (SDI) code, status matrix (SM) and range. Validity criteria for the ADIRU1, ADIRU2 and EIU input parameters are listed in tables 1, 2 and 3. If a parameter fails to meet any of the validity criteria for a continuous period greater than or equal to the ARINC fault delay, that parameter will be declared invalid by the ECU for its input selection logic and a message provided on the data bus output.

(a) Discrete ARINC Input Data Processing - Table 1

-------------------------------------------------------------------------------

!Logic executed for each discrete word defined as an input to the ECU !

!-----------------------------------------------------------------------------!

!UPDATE TIME !Input word is rejected if update time is above !

! !max. limit. !

! ! !

!SDI VALIDITY !Input word is rejected if SDI does not have !

! !valid state. All SDI's from EIU are accepted as !

! !valid except for label 227. !

! ! !

!SM VALIDITY !Input word is rejected if SM is not 00. !

! ! !

!ARINC FAULT !Required duration of ARINC input fault before !

!DELAY !declaring word invalid (last valid input held !

! !during the delay). !

! ! !

!ARINC INPUT FAULT !Latched status flag which is set at the end of !

! !the fault delay !

!STATUS ARINC FAULT DELAY !to indicate type of fault(s). !

! ! !

!OUTPUT STATUS !A STATUS flag is set every logic iteration to !

! !indicate validation logic state. !

! ! !

!VALID OR HOLD INVALID ! !

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(2) Digital Input

(a) BCD ARINC Input Data Processing - Table 2

-------------------------------------------------------------------------------

!Logic executed for each BCD word defined as an input to the ECU is as follows!

!-----------------------------------------------------------------------------!

!UPDATE TIME !Input word is rejected if update time is above !

! !max. limit. !

! ! !

!SDI VALIDITY !Input word is rejected if SDI does not have !

! !valid state. All SDI's from EIU are accepted as !

! !valid except for label 227. !

! ! !

!SM VALIDITY !Input word is rejected if SM is not 11 or 00. !

! ! !

!ARINC FAULT !Required duration of ARINC input fault before !

!DELAY !declaring word invalid (last valid input held !

! !during the delay). !

! ! !

!ARINC INPUT FAULT !Input status of input parameter value is set to !

! !"good", "Range fault", or "Arinc fault". !

! ! !

!FUNCTIONAL RATE LIMIT !PV change is within rate limits for a parameter !

! !if limits exist. !

! ! !

!RATE LIMIT STATUS !PV status is set to rate limit if PV change !

! !if outside of limits. !

! ! !

!OUTPUT STATUS !PV status is set to "valid", "acquire", !

! !"invalid", "hold", or "rate fault" to indicate !

! !validation logic status. !

-------------------------------------------------------------------------------

(3) Digital Input

(a) Binary ARINC Input Data Validation - Table 3

-------------------------------------------------------------------------------

!Logic executed for each discrete word defined as an input to the ECU !

!-----------------------------------------------------------------------------!

!UPDATE TIME !Input word is rejected if update time is above !

! !max. limit. !

! ! !

!SDI VALIDITY * !Input word is rejected if SDI does not have !

! !valid state for ADIRU1, ADIRU2. All SDI's !

! !from EIU are accepted as valid except for !

! !label 227. !

! ! !

!SM VALIDITY !Input word is rejected if SM is not 11. !

! ! !

!RANGE !Input word is rejected if value is outside !

! !range limits. !

! ! !

!RANGE FAULT DELAY !Required duration of input range fault before !

! !declaring the parameter invalid (last valid !

! !input held during delay). !

! ! !

!ARINC INPUT !Latched status which is set at the end of ARINC !

!FAULT STATUS !FAULT DELAY to indicate fault type(s). !

! ! !

!INPUT STATUS !Status which is set every iteration to indicate !

! !input parameter and validation logic states. !

! ! !

!DELAYED INPUT !Latched status which is set at the end of RATE !

!FAULT STATUS !FAULT DELAY or RANGE FAULT DELAY to indicate !

! !fault type(s). !

! ! !

!RANGE LIMITS !Acceptable worst-case operating limits, !

! !including abnormal aircraft and engine !

! !operation. Set for the purpose of system fault !

! !detection. !

! ! !

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(4) Digital Output

(a) General
Bit transmission rate is nominally 12.5 kHz. Each channel of the ECU has two output ports and each bus has separate line drivers.
Outputs are isolated in such a way that propagation of failures is prevented.
Information contained on FADEC output buses includes the following general items:

Engine Rating Parameter Information
Parameters used for Engine Control
FADEC System Maintenance Data
Engine Condition Monitoring Parameters
ECU Status and Fault Indication.

A detailed list of the specific data items on the output data buses is shown in Tables 4 to 22.

(b) ECU ARINC Output Bus Data (Binary) - Table 4

-----------------------------------------------------------------------

! ! ! MAX ARINC !Binary!Significant! Operating ! !

!Parameter !label! Update ! ! ! range ! units !

! ! !Time (msec)!Range ! Bits * ! Min.! Max. ! !

!-----------!-----!-----------!------!-----------!-----!------!-------!

!Selected ! ! ! ! ! ! ! !

!TLA ! 133 ! 125 ! 1 ! 12 ! -25 ! +55 !degrees!

!T12 ! 130 ! 250 ! 128 ! 11 ! -55 ! 85! deg.C !

!Selected ! ! ! ! ! ! ! !

!T25 ! 263 ! 250 ! 256 ! 12 ! -55 ! 120! deg.C !

!T3 ! 265 ! 250 !1.024 ! 12 ! -55 ! 850! deg.C !

!Selected ! ! ! ! ! ! ! !

!T495 ! 345 ! 125 !2.048 ! 12 ! -55 ! 1.200! deg.C !

!T5 ! 260 ! 250 !1.024 ! 12 ! -55 ! 850! deg.C !

!Selected ! ! ! ! ! ! ! !

!Flex ! ! ! ! ! ! ! !

!Temperature! 214 ! 250 ! 128 ! 16 ! -55 ! 85! deg.C !

!Engine Oil ! ! ! ! ! ! ! !

!Temp ! 316 ! 1.000 !2.048 ! 12 ! -55 ! 170! deg.C !

!ECU ! ! ! ! ! ! ! !

!Temperature! 304 ! 1.000 ! 256 ! 12 ! -55 ! 125! deg.C !

!Selected ! ! ! ! ! ! ! !

!HPTC Temp. ! 116 ! 500 !1.024 ! 12 ! -55 ! 850! deg.C !

!Selected Po! 114 ! 250 ! 32 ! 12 ! 2 ! 20! psia !

!PT2 ! 131 ! 250 ! 32 ! 12 ! 1.75! 22! psia !

!PS13 ! 127 ! 250 ! 32 ! 12 ! 2 ! 30! psia !

!PS12 ! 217 ! 480 ! 32 ! 12 ! 2 ! 30! psia !

!P25 ! 262 ! 250 ! 64 ! 12 ! 2 ! 50! psia !

!Selected ! ! ! ! ! ! ! !

!PS3 ! 264 ! 125 ! 512 ! 12 ! 2 ! 512! psia !

!FMV Demand ! 060 ! 125 ! 128 ! 12 ! 0 ! 100!percent!

!Eng on time! 050 ! 1000 ! 65535! 17 ! 0 ! 65535! hours !

!VSV Demand ! 061 ! 250 ! 64 ! 12 ! -3.8! 38.71!degrees!

!VBV Demand ! 062 ! 250 ! 64 ! 12 ! 0 ! 40!degrees!

!HPTC Demand! 063 ! 500 ! 128 ! 12 ! 0 ! 100!percent!

!LPTC Demand! 064 ! 500 ! 128 ! 12 ! 0 ! 100!percent!

!RACSB Demnd! 057 ! 500 ! 128 ! 12 ! 0 ! 100!percent!

!N1 actual ! 054 ! 500 ! 256 ! 13 ! 0 ! 120!percent!

!selected ! ! ! ! ! ! ! !

!RACSB ! ! ! ! ! ! ! !

!Position ! 055 ! 500 ! 128 ! 12 ! 0 ! 100!percent!

!VBV Torque ! ! ! ! ! ! ! !

!Motor ! 052 ! 250 ! 512 ! 12 !-300 ! 300! mA !

!N1 ! ! ! ! ! ! ! !

!Reference ! 166 ! 125 ! 256 ! 12 ! 0 ! 108!percent!

! ! ! ! ! ! ! !RPM !

-----------------------------------------------------------------------

* Does not include sign

(5) Digital Output

(a) ECU ARINC Output Bus Data (Binary) - Table 5

-----------------------------------------------------------------------

! ! ! MAX ARINC !Binary!Significant! Operating ! !

!Parameter !label! Update ! ! ! range ! units !

! ! !Time (msec)!Range ! Bits * ! Min.! Max. ! !

!-----------!-----!-----------!------!-----------!-----!------!-------!

!Selected ! ! ! ! ! ! ! !

!FMV Posn. ! 347 ! 31 ! 128! 12 ! 0 ! 100!percent!

!Selected ! ! ! ! ! ! ! !

!VBV Posn. ! 071 ! 250 ! 64! 12 ! 0 ! 40!degrees!

!Selected ! ! ! ! ! ! ! !

!VSV Posn. ! 072 ! 125 ! 64! 12 !-5.8 ! 38.71!degrees!

!Selected ! ! ! ! ! ! ! !

!HPTC Posn. ! 306 ! 500 ! 128! 12 ! 0 ! 100!percent!

!Selected ! ! ! ! ! ! ! !

!LPTC Posn. ! 307 ! 500 ! 128! 12 ! 0 ! 100!percent!

!WFM ! 244 ! 500 !32.768! 16 ! 0 !15.000! pph !

!N1 ! ! ! ! ! ! ! !

!Indicated ! 346 ! 63 ! 256! 13 ! 0 ! 120!percent!

! ! ! ! ! ! ! !RPM !

!Selected N2! ! ! ! ! ! ! !

!Actual ! 344 ! 63 ! 256! 13 ! 0 ! 120!percent!

! ! ! ! ! ! ! !RPM !

!N1 Maximum ! 342 ! 250 ! 256! 14 ! 0 ! 102.0!percent!

! ! ! ! ! ! ! !RPM !

!N1 Limit ! 337 ! 125 ! 256! 14 ! 0 ! 102.0!percent!

! ! ! ! ! ! ! !RPM !

!N1 Command ! 341 ! 125 ! 256! 14 ! 0 ! 102.0!percent!

! ! ! ! ! ! ! !RPM !

!N1 Target ! ! ! ! ! ! ! !

!F/B ! 343 ! 125 ! 256! 14 ! 0 ! 102.0!percent!

! ! ! ! ! ! ! !RPM !

!FMV Tm ! ! ! ! ! ! ! !

!Demand ! 300 ! 63 ! 512! 12 !-300 ! 300! mA !

!LPTC Tm ! ! ! ! ! ! ! !

!Demand ! 301 ! 500 ! 512! 12 !-300 ! 300! mA !

!VSV Tm ! ! ! ! ! ! ! !

!Demand ! 302 ! 125 ! 512! 12 !-300 ! 300! mA !

!Selected PT! 242 ! 250 ! 2.048! 12 ! 135 ! 1379! mb !

!Selected Q ! 215 ! 250 ! 512! 12 ! 0 ! 450! mb !

!Selected ! ! ! ! ! ! ! !

!TAT ! 211 ! 250 ! 512! 11 ! -60 ! 99! deg.C !

!Mo ! 205 ! 250 ! 4.096! 12 ! 0.0 ! 1.000! mach !

!Calc. Bleed! 303 ! 250 ! 64! 12 ! 0.0 !20.0 ! pps !

!Engine S/N ! 046 ! 1.000 ! NA ! NA ! NA ! NA ! LSD's !

!Engine S/N ! 047 ! 1.000 ! NA ! NA ! NA ! NA ! MSD's !

-----------------------------------------------------------------------

(6) Digital Output

(a) ECU ARINC Output Bus Data (Discrete) - Table 6

------------------------------------------------

! ! ! MAX ARINC !

! Parameter ! label ! Update Time !

! ! ! Max. (msec) !

!---------------------!----------!-------------!

! ECU Status Word 1 ! 270 ! 250 !

! Engine Rating Word ! 271 ! 1.000 !

! ECU Status Word 2 ! 272 ! 250 !

! ECU Status Word 3 ! 273 ! 125 !

! ECU Status Word 4 ! 274 ! 125 !

! ECU Status Word 5 ! 275 ! 125 !

! Maintenance Word 1 ! 350 ! 500 !

! Maintenance Word 2 ! 351 ! 500 !

! Maintenance Word 3 ! 352 ! 500 !

! Maintenance Word 4 ! 353 ! 500 !

! Maintenance Word 5 ! 354 ! 240 !

! Maintenance Word 6 ! 355 ! 250 !

! Fault Data Word ! 356 ! 125 (3)!

! Internal status word! 011 ! 1000 !

------------------------------------------------

NOTE: 1- Maintenance word 6(355) conveys no data in the data field (bits 11) through 29 all set to zero.
2- Refresh time is 62.5 ms in the menu mode.

(7) Digital Output

(a) ECU Status Word 1 - Label 270 ECU ARINC Output Bus Data (Discrete) - Table 7

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Ignition 1 Primary Selected !

! 12 ! Starter Shutoff Valve Switch Fault

! 13 ! Starter Shutoff Valve Open - Local Switch

! 14 ! HP Fuel Valve Closed - Local Switch !

! 15 ! SAV Demand/Position Disagree !

! 16 ! HPSOV Demand/Position Disagree !

! 17 ! Start EGT Overtemperature Detected !

! 18 ! Start Stall Detected !

! 19 ! No/Low Fan Speed for Core Speed !

! 20 ! No Engine Lightoff Detected !

! 21 ! Starter Time Limit Exceeded !

! 22 ! Fuel Schedule Derich Active !

! 23 ! TLA Not At Idle for Start Initiation !

! 24 ! Channel in Control !

! 25 ! Low Sap - (Slow Start) Detected !

! 26 ! Start Abort Active !

! 27 ! New Start in Progress !

! 28 ! 50 percent Thrust Limit Active !

! 29 ! HP Fuel Valve Switch Fault !

------------------------------------------------------------------------------

(8) Digital Output

(a) Engine Rating Word - Label 271 ECU ARINC Output Bus Data (Discrete) - Table 8

-----------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!---------------------------------------------------------!

! 11 ! SAVPOS Isolated Fault !

! 12 ! HPSOVPOS Isolated Fault !

! 13 ! TRPVPOS Isolated Fault !

! 14 ! OILTEMP Isolated Fault !

! 15 ! TLASST Isolated Fault !

! 16 ! TRDVCWFLTL Isolated Fault !

! 17 ! Engine Rating Least Significant Bit !

! 18 ! Engine Rating Bit 1 !

! 19 ! Engine Rating Bit 2 !

! 20 ! Engine Rating Bit 3 !

! 21 ! Engine Rating Bit 4 !

! 22 ! CFM56-5B Engine Installed !

! 23 ! Wing Anti-Ice Commanded !

! 24 ! Bleed Constant K1 Commanded !

! 25 ! Bleed Constant K2 Commanded !

! 26 ! Bleed Constant K3 Commanded !

! 27 ! Bleed Constant K4 Commanded !

! 28 ! Bleed Constant K5 Commanded !

! 29 ! Bleed Constant K6 Commanded !

-----------------------------------------------------------------

(b) ECU Status Word 2 - Label 272 ECU ARINC Output Bus Data (Discrete) - Table 9

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Master Lever OFF !

! 12 ! Bump/Overboost 1 Enabled !

! 13 ! Bump/Overboost 2 Enabled !

! 14 ! Bump/Overboost 3 Enabled !

! 15 ! Max Reverse Limit Mode Selected !

! 16 ! TLA MCT set to FTO !

! 17 ! BSVPOS Isolated Fault !

! 18 ! Bump/Overboost Active !

! 19 ! Auto Thrust Active !

! 20 ! Approach Idle Commanded !

! 21 ! Alpha Floor Protection Selected !

! 22 ! MTO. GA Limit Mode Selected! !

! 23 ! FLEX TAKEOFF Limit Mode Selected !

! 24 ! MCT Limit Mode Selected !

! 25 ! MCL Limit Mode Selected !

! 26 ! Engine Interface Unit Data Fault !

! 27 ! Autothrust Disconnect Commanded !

! 28 ! Aircraft on Ground !

! 29 ! Minimum Power Active !

------------------------------------------------------------------------------

(9) Digital Output

(a) ECU Status Word 3 - Label 273 ECU ARINC Output Bus Data (Discrete) - Table 10

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Manual Air Start N2 Less Than 10 percent !

! 12 ! Four TR Doors Not Stowed !

! 13 ! HP Fuel Valve Commanded Open !

! 14 ! RAC/TBV position isolated fault !

! 15 ! Category 2 Fault(s) !

! 16 ! LPTCPOS Isolated Fault !

! 17 ! Core Speed Below 15 Percent !

! 18 ! Core Speed At or Above 50 Percent !

! 19 ! Auto-Start Sequence in Progress !

! 20 ! Manual Start in Progress !

! 21 ! Wet Crank in Progress !

! 22 ! Dry Crank in Progress !

! 23 ! Continuous Ignition Active !

! 24 ! Blow Out Recovery Active !

! 25 ! Four T/R Doors Fully Stowed and Locked !

! 26 ! Four T/R Doors Fully Deployed !

! 27 ! 1, 2, or 3 T/R Door not Stowed !

! 28 ! Thrust Reverser System Pressurized !

! 29 ! Start Assist Fail - Emer W/M Start Sel !

------------------------------------------------------------------------------

(10) Digital Output

(a) ECU Status Word 4 - Label 274 ECU ARINC Output Bus Data (Discrete) - Table 11

-----------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!---------------------------------------------------------!

! 11 ! TRPV Demend/Position Disagree !

! 12 ! TR Pressure Switch Fault !

! 13 ! 115 VAC to Ignition exciter 1 Commanded !

! 14 ! Ignition System 1 Fault !

! 15 ! 115 VAC to Ignition exciter 2 commanded !

! 16 ! Ignition System 2 Fault !

! 17 ! SAV Open Command !

! 18 ! Burner Staging on 10 Nozzles Commanded !

! 19 ! BSV Demand/Position Disagree !

! 20 ! BSV Switch Fault !

! 21 ! RAC or TBV Demand/Position Feedback Disagree !

! 22 ! TR Stow Switch Circuit Failure !

! 23 ! Engine Oil Temp High Fault !

! 24 ! TR Deploy Switch Circuit Failure !

! 25 ! TR Inderteminable SW Circuit Failure !

! 26 ! TR Deploy Commanded !

! 27 ! TR Pressurize Commanded !

! 28 ! TR Auto Restow Commanded or TR locks failed !

! 29 ! LPTC Demand/Position Feedback Disagree !

-----------------------------------------------------------------

(11) Digital Output

(a) ECU Status Word 5 - Label 275 ECU ARINC Output Bus Data (Discrete) - Table 12

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! FRV Commanded Open at Second Level !

! 12 ! Reserved for FWC !

! 13 ! Spare !

! 14 ! FMV Demand/Position Feedback !

! 15 ! N1/N2 Control Active !

! 16 ! FMVPOS Isolated Fault !

! 17 ! VBV position fault latched !

! 18 ! VBV position fault !

! 19 ! VSV position fault latched !

! 20 ! VSV position fault !

! 21 ! RAC in bleed: position fault latched !

! 22 ! RAC in bleed: position fault !

! 23 ! ECU Designation Discretes Invalid !

! 24 ! Engine ID Plug Fault !

! 25 ! FRV Commanded Open at First Level !

! 26 ! Channel A Active !

! 27 ! Channel B Active !

! 28 ! All Channel Controls Active !

! 29 ! HPTC Demand/Position Feedback Disagree !

------------------------------------------------------------------------------

(12) Digital Output

(a) ECU Maintenance Word 1 - Label 350 ECU ARINC Output Bus Data (Discrete) - Table 13

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! TAT ADC1 Input Not Used !

! 12 ! PO ADC1 Input Not Used !

! 13 ! PT ADC1 Input Not Used !

! 14 ! HPTPOS Isolated Fault !

! 15 ! TAT ADC2 Input Not Used !

! 16 ! PO ADC2 Input Not Used !

! 17 ! PT ADC2 Input Not Used !

! 18 ! Cross Channel TLA Input Fault !

! 19 ! Local Channel TLA Input Fault !

! 20 ! TLA Input Inequality Fault !

! 21 ! TRDV Aircraft switch Fault !

! 22 ! Thrust Reverser Position Fault !

! 23 ! TRPV Sol Wrap Fault/HCU Clog Detection !

! 24 ! TR Directional VLV Solenoid Wrap Fault !

! 25 ! ECU Overtemperature Isolated Fault !

! 26 ! Aircraft 28 Volts Power Unavailable !

! 27 ! Instinctive Disconnect Fault !

! 28 ! 115 VAC to Ignition exciter 1 unavailable !

! 29 ! 115 VAC to Ignition exciter 2 unavailable !

------------------------------------------------------------------------------

(b) ECU Maintenance Word 2 - Label 351 ECU ARINC Output Bus Data (Discrete) - Table 14

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Flex Temperature Input Invalid !

! 12 ! A/T N1 Target Input Invalid !

! 13 ! ECS Mod Idle Input Invalid !

! 14 ! Bleed Const. - 030 EIU Input Invalid !

! 15 ! A/C Discrete - 031 EIU Input Invalid !

! 16 ! Autothrust - 034 EIU Input Invalid !

! 17 ! CFDS Signal - 227 EIU Input Invalid !

! 18 ! FMV Input Inequality Fault !

! 19 ! VSV Input Inequality Fault !

! 20 ! VBV Input Inequality Fault !

! 21 ! HPTC Input Inequality Fault !

! 22 ! Flight Number Input Invalid !

! 23 ! Date Input Invalid !

! 24 ! GMT Input Invalid !

! 25 ! RAC/TBV Input Inequality Invalid !

! 26 ! LPTC Input Invalid !

! 27 ! PS13 Input Invalid !

! 28 ! TECU Input Invalid !

! 29 ! Fuel Flow Measurement Invalid !

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! T12 Input Invalid !

! 12 ! T25 Input Invalid !

! 13 ! T495 Input Invalid !

! 14 ! HPTC T/C Input Invalid !

! 15 ! Reserved for A/C T25 Fault Use !

! 16 ! PO Input Invalid !

! 17 ! PT2 Input Invalid !

! 18 ! PS3 Input Invalid !

! 19 ! PS3 Local/Model Disagree !

! 20 ! N1 and N2 Feedback Invalid !

! 21 ! N1 Input Invalid !

! 22 ! N2 Input Invalid !

! 23 ! T3 Input Invalid !

! 24 ! T5 Input Invalid !

! 25 ! Reserved for A/C N1 Fault Use !

! 26 ! TE0 Input Invalid !

! 27 ! P25 Input Invalid !

! 28 ! Reserved for A/C N2 Fault Use !

! 29 ! Reserved for A/C T3 Fault Use !

------------------------------------------------------------------------------

(d) ECU Maintenance Word 4 - Label 353 ECU ARINC Output Bus Data (Discrete) - Table 16

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! FMV Feedback Invalid !

! 12 ! FMV Torque Motor Wrap Fault !

! 13 ! VBV Feedback Invalid !

! 14 ! VBV Torque Motor Wrap Fault !

! 15 ! VSV Feedback Invalid !

! 16 ! VSV Torque Motor Wrap Fault !

! 17 ! HPTC Feedback Invalid !

! 18 ! HPTC Torque Motor Wrap Fault !

! 19 ! SAV Solenoid Wrap Fault !

! 20 ! T495 Input Inequality Fault !

! 21 ! LPTC Feedback Invalid !

! 22 ! LPTC Torque Motor Wrap Fault !

! 23 ! BSV Solenoid Wrap Fault !

! 24 ! TC Input Inequality Fault !

! 25 ! TEO Input Inequality Fault !

! 26 ! RAC/TBV Feedback Invalid !

! 27 ! RAC/TBV Torque Motor Wrap Fault !

! 28 ! OSG Fault !

! 29 ! Alternator Fault !

------------------------------------------------------------------------------

(e) ECU Maintenance Word 5 - Label 354 ECU ARINC Output Bus Data (Discrete) - Table 17

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! ARINC 1 Output Wrap Fault !

! 12 ! Cross Channel Data Serial Bus Fault !

! 13 ! Non-Volatile Memory Fault !

! 14 ! Cross Channel Data Link Parallel Disc Fault !

! 15 ! Reserved, Used in A/C FADEC Overtemp Fault !

! 16 ! FRV2 Solenoid Wrap Fault !

! 17 ! FRV1 Solenoid Wrap Fault !

! 18 ! Wow Inputs Disagree !

! 19 ! Signal Conversion Fault !

! 20 ! Spare !

! 21 ! Local Channel Major Internal Fault !

! 22 ! T/C Cold Junction Compensation Fault !

! 23 ! Local Channel Major Internal Fault !

! 24 ! Cross Channel Major Internal Fault !

! 25 ! ECU Local Channel Fault !

! 26 ! ECU Temperature Limit Exceeded !

! 27 ! Autothrust Inoperative !

! 28 ! FRV Switch Fault !

! 29 ! 28 VDC Disconnect Command !

------------------------------------------------------------------------------

(13) Digital Output

(a) ECU Maintenance Word 6 - Label 355 ECU ARINC Output Bus Data (Discrete) - Table 18

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Core Speed at or above N2 IDL !

! 12 ! Autothrust Memo Thrust Mode Active !

! 13 ! Idle Selected Due to Thrust Reverser Inadvertently Deployed !

! 14 ! Volontary autothrust Logic Active !

! 15 ! 28 VDC Fault !

! 16 ! 28 VDC Fault Due to EIU !

! 17 ! FRV Open position fault latched !

! 18 ! FRV Open position fault !

! 19 ! FRV Closed position fault latched !

! 20 ! FRV Closed position fault !

! 21 ! Engine Idle Set for Oil Temp Cooling !

! 22 ! Reserved for CFM56-5B Dual Annular C. !

! 23 ! Reserved for CFM56-5B Dual Annular C. !

! 24 ! Reserved for CFM56-5B Dual Annular C. !

! 25 ! Reserved for CFM56-5B Dual Annular C. !

! 26 ! Reserved for CFM56-5B Dual Annular C. !

! 27 ! Reserved for CFM56-5B Dual Annular C. !

! 28 ! Reserved for CFM56-5B Dual Annular C. !

! 29 ! Spare !

------------------------------------------------------------------------------

(14) Digital Output

(a) ECU Discrete Internal Status Word 1 (Label 011) ECU ARINC Output Bus Data (Discrete) - Table 19

------------------------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!----------------------------------------------------------------------!

! 11 ! Burner Staging Valve Position Status !

! 12 ! Regulator, Bit 1 !

! 13 ! Regulator, Bit 2 !

! 14 ! Regulator, Bit 3 !

! 15 ! Regulator, Bit 4 !

! 16 ! Regulator, Bit 5 !

! 17 ! Idle Regulator, Bit 1 !

! 18 ! Idle Regulator, Bit 2 !

! 19 ! Idle Regulator, Bit 3 !

! 20 ! Idle Regulator, Bit 4 !

! 21 ! ENGPNLMD Indicator Bit 1 !

! 22 ! ENGPNLMD Indicator Bit 2 !

! 23 ! ENGPNLMD Indicator Bit 3 !

! 24 ! ENGPNLMD Indicator Bit 4 !

! 25 ! Reserved for CFM56-5B Dual Annular C. !

! 26 ! Reserved for CFM56-5B Dual Annular C. !

! 27 ! Spare !

! 28 ! Spare !

! 29 ! Spare !

------------------------------------------------------------------------------

(15) Digital Output

(a) ARINC Label 046 FADEC Engine Serial No. BCD Output Word - Table 20

-----------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!---------------------------------------------------------!

! 11 ! Logic 1 !

! 12 ! Logic "0" !

! 13 ! Logic "0" !

! 14 ! Logic "0" !

! 15 ! LSB OF DIGIT 1 OF ENG SN. !

! 16 ! BIT 2 DIGIT 1 OF ENG SN. !

! 17 ! BIT 3 DIGIT 1 OF ENG SN. !

! 18 ! MSB OF DIGIT 1 OF ENG SN. !

! 19 ! LSB OF DIGIT 2 OF ENG SN. !

! 20 ! BIT 2 DIGIT 2 OF ENG SN. !

! 21 ! BIT 3 DIGIT 2 OF ENG SN. !

! 22 ! MSB OF DIGIT 2 OF ENG SN. !

! 23 ! LSB OF DIGIT 3 OF ENG SN. !

! 24 ! BIT 2 DIGIT 3 OF ENG SN. !

! 25 ! BIT 3 DIGIT 3 OF ENG SN. !

! 26 ! MSB OF DIGIT 3 OF ENG SN. !

! 27 ! Logic "0" !

! 28 ! Logic "0" !

! 29 ! Logic "0" !

! 30 ! Logic "0" (SM Bit) !

! 31 ! Logic "0" (SM Bit) !

-----------------------------------------------------------------

(16) Digital Output

(a) ARINC Label 047 FADEC Engine Serial No. BCD Output Word - Table 21

-----------------------------------------------------------------

! Bit ! Description (Bit = 1) !

! No. ! !

!-----!---------------------------------------------------------!

! 11 ! Logic 1 !

! 12 ! Logic "0" !

! 13 ! Logic "0" !

! 14 ! Logic "0" !

! 15 ! LSB OF DIGIT 4 OF ENG SN. !

! 16 ! BIT 2 DIGIT 4 OF ENG SN. !

! 17 ! BIT 3 DIGIT 4 OF ENG SN. !

! 18 ! MSB OF DIGIT 4 OF ENG SN. !

! 19 ! LSB OF DIGIT 5 OF ENG SN. !

! 20 ! BIT 2 DIGIT 5 OF ENG SN. !

! 21 ! BIT 3 DIGIT 5 OF ENG SN. !

! 22 ! MSB OF DIGIT 5 OF ENG SN. !

! 23 ! LSB OF DIGIT 6 OF ENG SN. !

! 24 ! BIT 2 DIGIT 6 OF ENG SN. !

! 25 ! BIT 3 DIGIT 6 OF ENG SN. !

! 26 ! MSB OF DIGIT 6 OF ENG SN. !

! 27 ! Logic "0" !

! 28 ! Logic "0" !

! 29 ! Logic "0" !

! 30 ! Logic "0" (SM Bit) !

! 31 ! Logic "0" (SM Bit) !

-----------------------------------------------------------------

(17) Digital Output

(a) Specification
Additional characteristics of the ECU digital output data buses are as follows:

1 Continuity
The ECU transmits the ARINC outputs on 4 buses; 2 per channel. The transmission is continuous on all the buses in normal operation irrespective of whether the given channel is in active control or not.
The data transmission is inhibited when the processor in the applicable channel is not functioning, during power-up or power-down transients, and during channel initialization.

2 Synchronization
The two ARINC output buses on a given channel are synchronized. The FIFOs in the two ARINC transmitters are loaded from a common software buffer. Thus in a given iteration step of 15 msec the same set of 5 ARINC labels will be transmitted on both output buses of a given channel with the same relationship with the real time clock interrupt of that channel. The two channels run on different cloks and the ECU Executive Software attempts to synchronize both channels at power-up and also on a continuous basis in normal operation. The two channels are, by design intent, synchronized to within approximately 20 microseconds. Thus the outputs of the two channels will be skewed equal to the channel synchronization error. If the two channels stay in synchronization continuously after power-up the same set of ARINC labels will be transmitted in a given computation frame by both channels.

3 Data
The values of parameters transmitted on the two output buses of a given channel are exactly the same. The parameter values output by the two channels are normally identical as long as the cross-channel data bus is functioning. Tables 4 and 5 show the parameters associated with the various output labels. Parameters such as selected TLA are based on a selection logic between the two available TLA inputs which is the same in both channels and thus would normally have the same value.
Parameters such as T12 with dual sensor inputs are based on the validated T12 input to that channel and thus due to normal sensor differences will have different values. Parameters such as T3 with single sensor input will have identical values on outputs of both channels as long as the cross-channel data bus is working. In the event of a failure of the cross channel data bus, the channel without T3 input information will output 0 (zero) on its ARINC buses.

4 Output differences
A wraparound check is performed on all the ARINC outputs whereby the output data is read back by the ECU and compared with the corresponding software buffer which is common for the two transmitters in a given channel. Thus if the two buses in a channel pass the wraparound test they will also be identical. If a given transmitter fails the wraparound test, all the subsequent ARINC parameters output on that bus will be flagged with an invalid Status Matrix (SM).
The other bus on the same channel will not be affected if it passes the wraparound test.
As stated in the "data" paragraph above, that data from the two channels is not necessarily exactly the same.

5 Channel switchover effect
The ECU ARINC outputs from all the four output buses continue to behave the same way after a channel switch as they do before. That is, both the channels will continue to process their outputs to reflect in corresponding input validation status and selection logic where applicable, processor/memory test and output validation status.
If these constituents do not change for a given parameter during a channel switchover that output will not be affected. For example in case of a channel switch from A to B due to a Fuel Metering Valve torque motor driver failure in Channel A, Channel A ARINC outputs for selected TLA, T12, Selected T25, and so on will not be affected.

6 Status matrix
The status matrix for the ARINC parameters is based on the following criteria:

a Discrete words

---------------------------------------------------

! 31 ! 30 ! !

!-----!-----!-------------------------------------!

! 0 ! 0 ! Normal Operation !

! 0 ! 1 ! No Computed Data !

! 1 ! 0 ! Functional Test !

! 1 ! 1 ! Failure Warning !

---------------------------------------------------

b Binary words

---------------------------------------------------

! 31 ! 30 ! !

!-----!-----!-------------------------------------!

! 0 ! 0 ! Failure Warning !

! 0 ! 1 ! No Computed Data !

! 1 ! 0 ! Functional Test !

! 1 ! 1 ! Normal Operation !

---------------------------------------------------

c BCD words (engine serial number labels 046,047)

---------------------------------------------------

! 31 ! 30 ! !

!-----!-----!-------------------------------------!

! 0 ! 0 ! Normal Operation !

! 0 ! 1 ! No Computed Data or Failure Warning !

! 1 ! 0 ! Functional Test !

! 1 ! 1 ! Not Used !

---------------------------------------------------

The status matrix of parameters affected by the requested test will be 1.0 during ground test. Parameters and data unaffected by the test will be set valid/invalid according to normal criteria.

7 Source/destination Identifier (SDI)
The SDI for the ARINC output words will be assigned based on the Engine Designation Discretes from the Airframe and the channel designation. The assignment matrix is as shown below.
Engine 1 channel A ECU sends a SDI 01 (BIT 10 - BIT 9)
Engine 1 channel B ECU sends a SDI 11 (BIT 10 - BIT 9)
Engine 2 channel A ECU sends a SDI 10 (BIT 10 - BIT 9)
Engine 2 channel B ECU sends a SDI 00 (BIT 10 - BIT 9)

(18) Discrete and Analog Signals
The ECU also receives discrete and analog signals from the airframe and from local engine sensors.

From airframe it receives:

(a) TLA signals
TLA validation logic is given in paragraph ECU/Trottle system interfaces.

(b) ECU reset:

ECU Reset ** ON A/C NOT FOR ALL

The ECU reset is associated to the ENG MASTER 1(2) lever switching. When lever is moved from ON to OFF position the ECU is reseted.

From engine it receives:
All the engine sensors signals are validated by the ECU - Basically The ECU checks the range limits, the rate limits and performs an interface fault detection.
From engine, the ECU also receives discrete signals to set the rating level and several options (Ref. AMM D/O 73-20-00-00).

B. ADIRU/ECU Interface

(1) General
ADIRU send air data parameters to the FADEC through ARINC 429 buses. One output ARINC 429 buses of each ADIRU is dedicated to one engine control only

Interwiring ECU-ADIRU ** ON A/C NOT FOR ALL

(2) Input Data to ECU
Data is provided from ADIRU to the ECU at "LOW BIT RATE" defined by ARINC 429 (12 - 14.5 kilobits per second). Air data transmitted to the FADEC will be in accordance with TABLE 23.

(a) ADIRU Data to FADEC - Table 23

------------------------------------------------------------------------------

! ! ! MAX ARINC ! Binary !Significant! Operating ! !

! Parameter !label! Update ! ! ! range !units!

! ! !Time (msec)! Range ! Bits ! Min.*! Max.* ! !

!----------------!-----!-----------!--------!-----------!------!-------!-----!

!Altitude ! 203 ! 62.5 !131.072 ! 17 !-1.000! 50.000!feet !

!Total Air Temp. ! 211 ! 500 !512 ! 11 ! -60.0! 99.0 !deg.C!

!Total Pressure ! 242 ! 125 ! 2.048 ! 16 ! ! ! mb !

!Discrete No. 1 ! 270 ! 500 ! NA ! - ! - ! - ! - !

!Discrete No. 2 ! 271 ! 500 ! NA ! - ! - ! - ! - !

!Mach Number (1)! 205 ! 125 ! 4096 ! 16 ! 0 ! 1 ! - !

------------------------------------------------------------------------------

Note (1): Transmitted only from ADC 1

NOTE: . Values differ from ARINC 706-3
. ADC 1 sends SDI 0 1 (BIT 10 - BIT 9)
. ADC 2 sends SDI 1 0 (BIT 10 - BIT 9)

The ECU reads up to the 16 most significant BIT:

(3) Data Validation and Selection Logic
The ECU performs validation test and selection logic between data coming from ADIRU and data from engine sensors, with the requirement that ADIRU inputs are preferred over engine sensors inputs, and used for rating calculations-otherwise engine sensor values will be used.
As an exception to that rule and only for operational purpose, it is acceptable that in case of complete loss of FADEC air data sensor, the corresponding value from the remaining ADIRU be used.
The involved air data parameters used to validate Po, PT, TAT and calculate Mo, altitude, ambient temperature used in power management and engine control are:

Total Air Temperature !

Total Air Pressure ! from ADIRU1 and ADIRU2

Altitude !

Po Ambient Pressure _!

PT12 Air Inlet Pressure -! from local and Cross Channel

T12 Total Air Inlet Temperature _!

General arrangement of validation and selection logic are referenced

Parameters Validation and Selection Logic ** ON A/C NOT FOR ALL

ARINC validation and sensor validations are given on TABLE 24.

(a) ADIRU'S Data Validation - Table 24

-------------------------------------------------------------------------------

! WORD LABEL ! ALTITUDE !TOTAL !TOTAL PRESSURE! MN !

! ! !AIR TEMP ! ! !

!--------------------------------!------------!-----------!--------------!----!

!BINARY DATA WORD LABEL ! 203 ! 211 ! 242 ! 205!

!FUNCTION ITERATION TIME (msec) ! 240 ! 240 ! 240 ! 140!

!ARINC UPDATE TIME LIMIT (msec) ! 180 ! 720 ! 180 ! 125!

!VALID SDI CODE(S) Bit 10, Bit 9 ! 01 ! 01 ! 01 ! !

!VALID SM CODE(S) ! 11 ! 11 ! 11 ! 11 !

!INPUT CONVERSION FUNCTION ! (Note 1) ! (Note 2)! (Note 3) ! !

!RANGE FAULT LIMIT - Min ! -2.000 ft.!-60.0 deg.C! 1.75 psia ! 0.1!

! - Max ! 50.000 ft.!+99.0 deg.C! 22.0 psia ! 1 !

!ARINC FAULT DELAY (msec) ! 480 ! 1920 ! 480 ! 480!

!LATCHED RANGE FAULT DELAY (msec)! 480 ! 1920 ! 480 ! 480!

!PARAMETER DEFAULT VALUE ! 14.696 psia! 15.0 deg.C! 14.696 psia ! 0.0!

-------------------------------------------------------------------------------

NOTE: . POADC1 = 14.696 (1-6.8756 x 10exp.-6 (Data Field)) exp.5.25588 psia
. TATADC1 = (Data Field) deg.C
. PTADC1 = 0.014504 (Data Field) psia
. Calculations may be directly implemented or via scheduled conversion.

C. EIU/ECU Interface

(1) General

(a) EIU Presentation
Two EIU's are fitted on each aircraft, one for engine 1, one for engine 2. Each EIU located in the electronics bay is an interface concentrator between the airframe and the corresponding FADEC located on the engine, reducing thus the number of wires. EIU's are active as soon as the aircraft electrical network is energized and stopped when the aircraft network is de-energized ; their operation is a necessary condition to start the engine.
The main functions of the EIU are:

to concentrate data from cockpit panels and different electronic boxes to the associated FADEC on each engine,
to insure the segregation of the two engines,
to select the airframe electrical supplies for the FADEC,
to give to the airframe the necessary logic and information from engine to other systems (APU, ECS, Bleed Air, Maintenance).

(b) EIU/ECU Interface
Data link arrangement between EIU and ECU is shown in

ECU - EIU Digital Data Unit ** ON A/C NOT FOR ALL

1 EIU input from the ECU
The EIU acquires two ARINC 429 output data buses from the associated ECU (one from each channel) and it reads data from the channel in control. When some data are not available on the channel in control, data from the other channel are used. The data flow is defined in tables 25 to 27.
The EIU will use Label 275 bit 26 and 27 on the ECU ARINC output buses to determine which channel is in control.
In the case where EIU is not able to identify the channel in control because of wrong setting of these bits, it will assume Channel A is in control.
The EIU will look at particular engine data on the ECU digital data flow to interface them with other aircraft computers and with engine cockpit panels.

2 EIU output to the ECU
Through its output ARINC 429 data bus, the EIU transmits data coming from all the computers which have to communicate with the ECU, except from ADIRU's and throttle control levers which communicate directly the ECU.
The contents of the digital data flow in normal operation is detailed on tables 25 to 27.
There is no data flow during EIU internal test or initialization.
The specific data outputs from EIU to ECU are given on tables 25 to 28.
The ECU performs the data validation according to ARINC data validation described in Para. 2A.

a Engine Interface Unit Data to ECU - Table 25

-------------------------------------------------------------------------------

! LABEL NAME ! FLEX TEMP !ECS MIN PRESS ! N1 TARGET !

! ! ! DEMAND ! !

!--------------------------------!--------------!--------------!--------------!

!BINARY DATA WORD LABEL ! 214 ! 222 ! 343 !

!FUNCTION ITERATION TIME (msec) ! 240 ! 60 ! 60 !

!ARINC UPDATE TIME LIMIT (msec) ! 720 ! 180 ! 180 !

!VALID SDI CODE(S) !00, 01, 10, 11!00, 01, 10, 11!11, 01, 10, 11!

!VALID SM CODE(S) ! 11 ! 11 ! 11 !

!INPUT CONVERSION FUNCTION ! (Note 1) ! (Note 2) ! (Note 3) !

!RANGE FAULT LIMIT - Min !-99.9 deg.C ! -1.0 percent ! 0 RPM !

! - Max !-99.9 deg.C !101.0 percent ! 5434 RPM !

!FUNCTIONAL RATE LIMIT - Decr. ! None ! None ! 500 RPM/sec!

! - Incr. ! None ! None ! 1.000 RPM/sec!

!ARINC FAULT DELAY (msec) ! 1920 ! 480 ! 480 !

!LATCHED RANGE FAULT DELAY (msec)! 1920 ! 480 ! 480 !

!PARAMETER DEFAULT VALUE (NOTE 4)! PRIOR VALUE !100.0 percent ! PRIOR VALUE !

-------------------------------------------------------------------------------

NOTE: TFLXEIU = (Data Field) deg.C.
ECSDEIU = (Data Field) percent.
ATNDEIU = 50.0 (Data Field) RPM.
Default values for label 343 are for reference. See logic.

3 Engine Interface Unit Data to ECU - Table 26

-----------------------------------------------------------------

! LABEL NAME ! GMT ! DATE !

!---------------------------------!--------------!--------------!

!BCD DATA WORD LABEL ! 125 ! 260 !

!FUNCTION ITERATION TIME (msec) ! 240 ! 240 !

!ARINC UPDATE TIME LIMIT (msec) ! 1000 ! 1000 !

!VALID SDI CODE(S) BIT 10, 9 !00, 01, 10, 11!00, 01, 10, 11!

!VALID SM CODE(S) ! 00, 11 ! 00, 11 !

!INPUT CONVERSION FUNCTION ! (Note 1) ! (Note 2) !

!RANGE FAULT LIMIT - Min ! 00:00.0 ! None !

! - Max ! 23:59.9 ! None !

!ARINC FAULT DELAY (msec) ! 480 ! 480 !

!LATCHED RANGE FAULT DELAY (msec) ! 1920 ! 480 !

!PARAMETER DEFAULT VALUE ! All Zeros ! All Zeros !

-----------------------------------------------------------------

NOTE: GMT = (Data Field) hours : minutes per ARINC 429-7.
DATE = (Data Field) per ARINC 429-7.

4 Discrete Input Signals - Table 27

-------------------------------------------------------------------------------

!DISCRETE!ARINC ! ! ! ARINC! DISCRETE COMMAND (TRUE = BIT 1) !

! ARINC !UPDATE! VALID ! VALID ! FAULT!--------------------------------------!

! WORD !TIME ! SDI ! SM ! DELAY!BIT!MNEMONIC! FUNCTION !DEFAULT!

! LABEL !LIMIT-!CODE(S)!CODE(S)!(msec)!NO.! ! ! STATE !

! !(msec)! ! ! ! ! ! ! !

!--------!------!-------!-------!------!---!--------!-----------------!-------!

! 030 ! 720 !Note 3 ! 00.11 ! 720 !12 ! BCK1 !Bleed Config. K1 ! 0 !

! ! ! ! ! !13 ! BCK2 !Bleed Config. K2 ! 0 !

! ! ! ! ! !14 ! BCK3 !Bleed Config. K3 ! 0 !

! ! ! ! ! !15 ! BCK4 !Bleed Config. K4 ! 0 !

! ! ! ! ! !16 ! BCK5 !Bleed Config. K5 ! 0 !

! ! ! ! ! !17 ! BCK6 !Bleed Config. K6 ! 0 !

! 031 ! 360 !Note 3 ! 00.11 ! 360 !11 ! IGON !Ignition On ! 0 !

! ! ! ! ! ! ! !Selected ! !

! ! ! ! ! !12 ! AUTO !Auto ! 0 !

! ! ! ! ! ! ! !Selected ! !

! ! ! ! ! !13 ! CRNK !Crank Selected ! 0 !

! ! ! ! ! !14 ! MLON !Master control ! 0 !

! ! ! ! ! ! ! !switch ON ! !

! ! ! ! ! !15 ! MLOF !Master control ! 0 !

! ! ! ! ! ! ! !switch OFF ! !

! ! ! ! ! !16 ! MSTR !Manual Start ! 0 !

! ! ! ! ! ! ! !Selected ! !

! ! ! ! ! !17 ! WOWT LH!Weight-On-Wheels ! 0 !

! ! ! ! ! ! ! !(True) ! !

! ! ! ! ! !18 ! WOWT RH!Weight-On-Wheels ! 0 !

! ! ! ! ! ! ! ! (True) ! !

! ! ! ! ! !19 ! SLIM !Slat Lever "In" ! 0 !

! ! ! ! ! !20 ! APIL !Mod Idle ! 0 !

! ! ! ! ! ! ! !Selected ! !

! ! ! ! ! !22 ! FRCL !Fuel ! 0 !

! ! ! ! ! ! ! !Recirculation OFF! !

! ! ! ! ! !24 ! !Overboost OFF ! !

! ! ! ! ! !25 ! !Overboost ON ! !

! ! ! ! ! !27 ! !28VDC OFF ! !

! ! ! ! ! !29 ! !Wing AI OFF ! !

! 034 ! 360 !Note 3 ! 00.11 ! 360 ! ! ! ! !

! ! ! ! ! !13 ! ATEN !Auto Throttle ! 0 !

! ! ! ! ! ! ! !Engaged ! !

! ! ! ! ! !14 ! ATON !Auto Throttle ! 0 !

! ! ! ! ! ! ! !Active ! !

! ! ! ! ! !23 ! !Alpha Floor ! !

! ! ! ! ! ! ! !Selected ! !

! 227 ! 1080 !Note 3 ! 00.11 ! 1080 !13-! ! ! !

! ! ! ! ! !24 ! EQPT !Equipment Code ! A11 0 !

! ! ! ! ! !24-! ! ! !

! ! ! ! ! !31 ! TMMD !Command Code ! A11 0 !

-------------------------------------------------------------------------------

NOTE: Function iteration times = 500 milliseconds for labels 030, 031 and 034.
Function iteration times = 100 milliseconds for label 227.
Validation SDI for ECUDSG=1 designation is 01 (Bits 10 and 9 respectively) and for ECUDSG=2 designation is 10 (Bits 10 and 9 respectively). All other SDI and ECUDSG combinations are invalid.

(2) EIU Description

(a) EIU inputs/outputs definition
The general EIU inputs/outputs arrangement is shown in

Engine Interface Unit ** ON A/C NOT FOR ALL

1 Inputs
The EIU receives discrete signal, ARINC 429 lines, analog voltage, electrical supplies and is able to process data from resistor sensors.
The EIU receives several ARINC 429 lines and is looking for specific information.

2 Outputs
The EIU sends discrete outputs and ARINC 429 line outputs ; one of the ARINC line is dedicated to the ECU and the other one to the A/C systems.

ARINC 429 Numerical Output Words ** ON A/C NOT FOR ALL

ARINC 429 Discrete Output Words ** ON A/C NOT FOR ALL

3 Functions of the EIU

a Input data validation
The EIU has to acquire the whole information available of the inputs without losses.
Transmitted messages must not be modified.
EIU receives two input buses (channel A and channel B) from the ECU, and reads data from in-control channel. When some data are not available on in-control channel, data from the other one are used.
EIU receives two input buses (primary and secondary) from ECS, and reads data from primary channel, if they are not available secondary channel is used. Except for label 061, the EIU uses only the data from secondary channel.
Some input signals are used to create output data ; when data is not available or in conflict with other sources, the correponding outputs are:

"open circuit" for discretes
"failure warning" for internal faults and "NCD" for external faults for ARINC data.

b Logics to be performed
The EIU has to perform the following logics with the acquired data:

discrete output: oil low press and ground light fault on

discrete output and digital ouput: APU boost valve closure for engines start TLA in T/O position

-processed logics:Modulated idle

28VDC airframe FADEC supply off

28VDC for FADEC fault

Engine 1, engine 2

APU boost fault

TLA in T/O position

Reverser inop

Oil low press inop

Fault inop

Valve closure for engine start inop

Master control switch fault

Crank/auto/ignition fault

Bump/overboost selection

Nacelle high temperature

Wing de-icing selection

Nacelle anti ice selection

APU boost command 1

APU boost command 2

FRSOV OFF selected

c Fault logics
The EIU incorporates an internal BITE allowing efficient fault detection. The result of that fault detection shall be contained in status and maintenance words available on the output data bus:

label 350
label 351
label 352

d Power-up tests
Power-up tests are accomplished only on the ground and if pressure switch indicates continuity to ground, in other cases initialization time is less than 20 ms.

D. EIU Power-up Test

(1) Conditions of Power-up Test Initialisation

(a) How long the computer must be de-energized:

1 sec.

(b) Aircraft configuration:

Aircraft on ground with engines stopped

(2) Progress of Power-up Test

(a) Duration:

3 sec. maximum

(b) Cockpit repercussions directly linked to power-up test accomplishment (some other repercussions may occur depending on the aircraft configuration but these can be disregarded):

none

(3) Results of Power-up test

(a) Test pass:

ECAM ENGINES page:
.engine parameters are displayed in green

(b) Test failed

MASTER CAUTION ON with gong
ECAM ENGINES page:
.amber XX are displayed in place of engine parameters
ECAM warning:
.ENG1 or ENG2 FADEC FAULT
or
.ENG1 or ENG2 FADEC A or B FAULT

(4) EIU/Aircraft Interface

(a) General environment
The EIU concentrates data from cockpit panels and different aircraft system to send them to the FADEC and gives selected FADEC information to the Aircraft systems. The EIU communicates with a lot of Aircraft systems through analog and digital interfaces.
The general architecture of the EIU/Aircraft interfaces is shown in

General Architecture ** ON A/C NOT FOR ALL

(b) AFCS interface

1 AFCS is part of the ATS function (Ref. AMM D/O 73-20-00-00).

2 The automatic flight system provides the following functions related to the engine power management.

compilation of N1 target
selection of autothrust modes
alpha floor protection
overboost selection
selection of flex T/O temperature

3 Input from AFS to the ECU is the data centralizer unit of the AFS and is linked to the EIU through an ARINC 429 low speed bus. The EIU then transmits this information to the ECU through the EIU/ECU digital data link.
The data link arrangement is shown in

AFS to ECU via EIU Wiring ** ON A/C NOT FOR ALL

Specific information from AFS is:

flex T/O temperature
auto-thrust airline signal
auto-thrust demand : N1 target
alpha floor protection signal
overboost select signals
auto thrust engagement signal.

4 Output to the AFS. The ECU sends directly some specific outputs to the AFS through the FADEC output bus via the FMGC which is part of AFS system. The data link arrangement is shown in

AFS to ECU via EIU Wiring ** ON A/C NOT FOR ALL

The EIU also receives these data from FADEC but does not transmit them to the AFS.
The following data are sent to the AFS:

- T/A - Confirmation at min idle

- N1 command - N1 throttle

- N1 actual - Fuel flow

- N1 target (feedback) - Bleed configuration

- N1 limit selected - Engine rating

- Thrust mode - Flex T/O temp

- N1 max

(c) ECS interface
The Environmental Control System (ECS) provides the following functions related to the engine control :

Engine bleed port pressure demand
Aircraft and engine bleed configuration

Engine bleed part pressure demand : The compatibility between ECS and Aircraft performance necessitates a modulation of the engine idle during the descent.
This modulation is obtained by controlling the bleed pressure at the high pressure port.
The ECS sends a signal representing a coefficient K which has to be used as follows.
(curve 2) + K (curve 1 - curve 2) = pressure demand
Bleed configuration shall be generated by the ECS with respect of the actual position of the various values

General Schematic of Air Bleeds ** ON A/C NOT FOR ALL

Through the logic

General Schematic of Air Bleeds ** ON A/C NOT FOR ALL

ECS determines multipliers for the various air bleed configurations.
The FADEC takes these multipliers into account for computation of thrust corrections.
The ECS demand for idle setting and multipliers corresponding to the bleed configuration is sent through ARINC 429 data bus via EIU to the ECU. Data link arrangement is referenced

Interface between ECS Computer via EIU and ECU ** ON A/C NOT FOR ALL

EIU receives two input buses (primary and secondary) from ECS and reads data from primary channel ; if they are not available, secondary channel is used.
Characteristics of these signals are described in

EIU Input from ECS ** ON A/C NOT FOR ALL

Bleed configuration is read from secondary channel only.

(d) Engine starting control panel interface
The engine control panel is controlled from engine panel located on the center pedestal which provides:

the ENG/MODE/CRANK/NORM/IGN START selector switch position,
the ENG/MASTER control switch position,

and receives the fault announcement
In addition, an engine manual start panel located on the overhead panel provides the "MAN start" signal to the ECU.
Input from engine start control panel to the EIU are discrete input signal

Discrete Input Output from EIU to A/C Starting Control ** ON A/C NOT FOR ALL

General arrangement is shown in

Inputs from Aircraft Starting Control to ECU ** ON A/C NOT FOR ALL

Output from EIU to engine starting panel is a discrete output signal

Discrete Input Output from EIU to A/C Starting Control ** ON A/C NOT FOR ALL

General arrangement is shown in

Ouputs from ECU to Aircraft A/C Starting Control ** ON A/C NOT FOR ALL

The electrical circuit diagram is shown in

Engine Control Power Supply for Ignition and Starting Systems ** ON A/C NOT FOR ALL

(e) CFDS interface
The centralized fault data system is a means of accessing the systems to obtain maintenance information and initiate tests through the BITE of the system.
The communication is established through the existing ARINC 429 bus arrangement

Centralized Fault Display System ** ON A/C NOT FOR ALL

The FADEC and EIU menu function is requested by the CFDS system through the label 227. The EIU depending on the equipment code, the EIU will work in menu mode or transmit the request to the ECU.

1 ECU transmission

a Normal mode
The ECU transmits the messages, if existing, contained in table according to the communication protocol (Ref. AMM D/O 31-30-00-00).

b Menu mode
The following functions can be selected:

current leg LRU data,
all leg LRU data,
all leg primary fault data,
FADEC system test,
ignition test,
Thrust reverser deployment test.

2 EIU transmission

a Normal mode
The EIU transmits the messages, if existing, according to the communication schedule (Ref. 31-32-00.

b Menu mode
The EIU deals only with the standard items of the menu which are:

last leg report,
previous leg report,
LRU identification.
Ground Scanning.

(f) Other interfaces
The EIU receives other signals from various systems listed below :

ANTI ICE ENG1, 2 pusbutton switch OFF position from cockpit panel.
ANTI ICE WING pusbutton switch OFF position from cockpit panel.
ENG/FADEC GND PWR pushbutton switch OFF position from cockpit panel.
Engine fire signal from the FDU.
Fuel recirculation shutdown from the FLSCU.
LH and RH landing gear compressed from LGCIU.
LH and RH landing gear released from LGCIU.
Engine selected from pin programming.
Oil pressure, quantity, temperature low press from engine sensor.
Nacelle temperature from engine sensor.
flaps and slats retracted from slat and flap levers.

All these inputs are shown in

Various EIU Inputs ** ON A/C NOT FOR ALL

The EIU sends some specific signals to various systems listed below:

APU boost - to the ECB.
2 signals of "Oil low press and ground" to FWC 1 (2) and panels.
Value closure to air valves.
HP fuel shut-off valve closed to the ECS.
TLA in T/O position.
Core speed at or above idle
Throttle control interlock
Thrust reverser inhibition

All these outputs are shown in

Discrete Outputs Signals ** ON A/C NOT FOR ALL

The EIU sends also the data bus output to the flight warning computer.

E. Cockpit System Display/ECU Interface

(1) General
The aircraft system which processes the engine data and messages for cockpit display on the cathode ray tubes consists in three display management computers (DMC) and two flight warning computers.
Each DMC receives 4 engine data buses, one from each channel of ECU and two from each engine. All the 8 buses from ECU engine 1 and ECU engine 2 are acquired by the 3 DMC'S. Each FWC receives 4 data buses one from each channel of ECU General Arrangement as shown in

Interwiring from FADEC to Cockpit Indications ** ON A/C NOT FOR ALL

(2) Functions
The engine parameters and messages are displayed on two ECAM CRT's. The upper ECAM display unit is dedicated permanently to the primary engine parameters

Upper ECAM Display Unit ** ON A/C NOT FOR ALL

The lower display unit is partly dedicated to engine parameters

Lower ECAM Display Unit ** ON A/C NOT FOR ALL

(a) Parameters indication
The cockpit system display will look for

Primary engine parameters : N1 actual, N1 limit, N1 command, N2, EGT and fuel flow. The single numerical N1 limit value which is displayed with the selected thrust limit mode is the result of a logic in the DMC which selects the highest one of the two engines.
Thrust reverser position signals.
HP fuel valve disagree signal.

(b) FADEC and engine health status
The single numerical Nl limit value which will be displayed with the selected thrust limit mode will be the result of a logic in the DMC which selects the hightest one (of the two engines) :

1 Thrust Reverser Position Signal

2 Disagree Signals (HP Fuel Shutoff Valve, Starter Air Valve)

3 FADEC and Engine health status:
health status shall be available to specify as a minimum:

a that one channel is out of order

b that FADEC operation is degraded by any combination of the following :

No power management - full engine control
Loss of key function - possible loss of engine control
Loss of Clearance Control - Increase in fuel consumption, EGT
Loss of function - function will not be available when commanded

with associated operating instruction when :

flight envelope or performance are limited
immediate action is required from pilot
maintenance action is required

c that FADEC is out of order leading to definitive IFSD

d that FADEC built-in engine limit protection is working with associated operating instruction.

e why FADEC is aborting starting sequence.
Table gives the detail of ECU status words and maintenance words whose discrete information can be used to generate the corresponding messages to be displayed:
Class 1 denotes fault for which a message has to be displayed during the flight because of operational consequences.
Class 2 denotes faults for which a message has to be displayed at the end of the flight because fault is significant.
Class 3 denotes faults for which no immediate message is required and maintenance action can be delayed.

F. Throttle Control System/ECU Interface

(1) General
Throttle control system is fully electrical, each throttle control lever shall drive two resolvers, located in the cockpit center pedestal, these resolvers are dedicated to the FADEC, one for each engine

Inputs from Throttle Control Lever Transducers to ECU ** ON A/C NOT FOR ALL

The FADEC excites and demodulates these resolvers.
Each throttle control lever is fitted with one pushbutton which is used to generate the autothrust disconnect discrete signal to the ECU

(2) Interface

(a) TLA signal
Throttle lever angle signals are sensed from resolvers rotated as a function of throttle control lever positions.
Electrical characteristics are as follows :

-------------------------------------------------------------------------------

PARAMETER VALUE

-------------------------------------------------------------------------------

Excitation 7.07 plus or minus 2 percent

VRMS

3.000 plus or minus 10

percent HZ

6 mA/23.5 mW

ZSO. Stator Impedance, Rotor open (0 degree) 215 + J395 ohms +/- 20

percent

ZSO. Stator Impedance, Rotor open (90 deg.C) 56 + J104 ohms +/- 20

percent

ZRO, Rotor Impedance, Stator open 650 + J980 ohms +/- 20

percent

ZSS, Stator Impedance, Rotor Shorted 54 + J128 ohms +/- 20

percent

Transformation Ratio 0.492 plus or minus 0.025

Phase Shift (Output to Input Voltage) 0.5 degrees +/- 2.0 degrees

Total Null Voltage 20 mV Max

Fundamental Null Voltage 15 mV Max

Electrical Error on Transmitter plus or minus 5 minutes Max

Electrical Error on Transmitter 6 minutes

(peak-to-peak)

There are two throttle resolvers per throttle control lever, each of them being dedicated to one channel of the ECU. The electrical excitation is provided by the ECU (one excitation output per channel).
The TLA resolver is a dual quadrant resolver which works in the first quadrant for positive angles and in the fourth quadrant for negative angles.
Therefore the TLA sine and cosine winding outputs are in phase with the excitation for resolver angle within 0 degree to 90 degrees range of angle.
In the -90 degrees to 0 degree range of angles the cosine output and the excitation are in phase and the sine output out of phase.

(b) Instinctive autothrust disconnect signal
The ECU receives a signal directly issued from either throttle control lever 1 or throttle control lever 2 pushbutton through an aircraft wiring

Autothrust Instinctive Disconnect ** ON A/C NOT FOR ALL

When instinctive disconnect pushbutton switch is pressed the minimum pulse duration has to be not less then 50 ms.

(3) TLA signal fault

(a) Fault detection
The TLA fault detection and validation logic are based on the following basic tests:

conversion range (Trigonometric Identity Test)
range tests (max and min limits)
rate check (in both increase or decrease directions)
TLA comparison (channel A to channel B has to be in 0.25 degree)

Detailed logic and values are given in

TLA Resolver Signal Processing ** ON A/C NOT FOR ALL

(b) Fault accomodation
The accomodation strategy is based on:

the objective to keep engine operationnal
the ECU capability to memorize value at the time of fault detection
the principle of using a throttle configuration allowing identification of the faulty value of TLA in case of disagreement between both channels

G. Thrust Reverser Interface

(1) General
The ECU controls the deployment and stowing sequence of the thrust reversers. The logic which is implemented in the ECU is based on TLA signals, flight ground signals, thrust reverser position feedback.
The general interwiring diagramm is given in

Thrust Reverser - FADEC Interwiring Diagram ** ON A/C NOT FOR ALL

The EIU authorizes the deployment of thrust reverser by the ECU based on TLA position signal set by SEC.

(2) Thrust reverser directional valve
The ECU interfaces with the thrust reverser directional valve (TRDV) solenoid. The solenoid contains two electrically isolated, independent windings, one dedicated to channel A and the other to channel B. Each of these windings conforms to the following characteristics:

Actuation current 300 mA Minimum

Actuation voltage 17.75 volts DC max. at 300 mA

Max. steady state voltage 31.5 volts DC

DC resistance 18 ohm min.

Sense

Energized T/R deploy

Deenergized T/R stow

Reactance (below 300 Hz) 500 millihenries nominal

ECU Update time 50 milliseconds min.

(3) Thrust Reverser Pressurizing Valve (TRPV) solenoid
Each channel within the ECU interfaces with the TRPV solenoid. The solenoid contains two electrically isolated, independent windings. One dedicated to channel A and the other to channel B. Each of these windings conforms to the following characteristics:

Actuation current 300 mA Minimum

Actuation voltage 18.24 volts DC max. at 300 mA.

Max. steady state voltage 31.5 volts DC

DC resistance 18 ohm min.

Sense

Energized Shutoff valve open

Deenergized Shutoff valve closed

Reactance (below 300 Hz) 500 millihenries nominal

ECU Update time 50 milliseconds min.

(4) Thrust reverser switches
Each channel of the FADEC interfaces with:

The 4 deploy switches, one on each doors which are fitted in serie.
The 4 stow switches are on each doors which are fitted in parallel.
The hydraulic pressure switch.

Each switch has electrical characteristics as follows:

open circuit voltage rating 50 VDC maximum

open circuit resistance 0.1 x 10exp.6 ohms min.

current 2 to 10 mA

maximum closed circuit resistance 5 ohms

** ON A/C NOT FOR ALL

3. Power Supply

A. 28 VDC Power Supply
The ECU is designed to operate with the engine not running, the ECU is operational 2 to 3 seconds after it is electrically powered by 28VDC aircraft electrical network through the ENG/FADEC GND PWR pushbutton switch. The ECU is electrically powered by the aircraft electrical network through the EIU.
The 28VDC permits:

automatic ground check of the FADEC before engine running,
engine starting,
powering the ECU while engine is running below 15 percent N2.

As soon engine is running above 15 percent N2 the FADEC automatically switches from aircraft electrical network power to the engine alternator power supply.
After engine shut down the ECU is powered by the aircraft 28 VDC network for 5 minutes to allow the engine parameters monitoring.
Channel A and B 28VDC power inputs are independent. Faults propagation between 28VDC and FADEC alternator inputs within each channel is prevented by design.
General schematic of 28VDC power is shown in

Electrical Power Supplies to FADEC ** ON A/C NOT FOR ALL

B. 115V AC Power Supply
The 115 VAC power supply is dedicated to the ignition exciters (Ref. AMM D/O 73-20-00-00).

** ON A/C NOT FOR ALL

4. FADEC Interfaces
All interfaces between ECU and engine sensors, LVDT'S feedback and HMU are detailed in section 73-20-00: ECU description.

** ON A/C NOT FOR ALL

5. Additional Engine Sensors

A. General
These additional engine sensors are optional and dedicated to the engine condition monitoring through the AIDS. These engine parameters (P13, P25, T3 and T5) are available on the ECU data bus output if installed on the engine.

B. T5 temperature Sensor

(1) General
The engine exhaust gas temperature is measured using a dual-thermocouple probe installed on the turbine frame, as the 4 o'clock location, aft looking forward. This probe contains 2 thermocouple junctions whose output lines embedded in compacted magnesia pass through a semi-rigid metallic tube also filled with compacted magnesia.
The parallel connection of the 2 lines is achieved within a connector located at 5:30 o'clock on the low pressure turbine case, aft looking forward.

(2) Description

T5 Temperature Sensor ** ON A/C NOT FOR ALL

The T5 temperature sensor consists of:

(a) A sensing element (probe) featuring

1 One metallic body containing the 2 thermocouple hot junctions and their lines.

2 One mounting flange for probe attachment to the turbine frame.
The flange has an integral eyelet for safetying of the 2 attachment bolts.

(b) A cable assembly featuring:

1 One semi-rigid metallic tube containing 2 chromel/alumel lines embedded in compacted magnesia.

2 One connector with a square flange for attachment to the engine.

(3) Operation
Each of the 2 thermocouples generates an electromotive force (FEM) which is proportional to the temperature surrounding their hot junction.
These FEM's are sent to the connector in which the 2 lines are connected in parallel. The resultant signal across the connector pins is then conveyed, via a chromel/alumel line, to a digital computer (Electronic Control Unit) for processing.

[Rev.10 from 2021] 2026.04.01 02:59:40 UTC