--------------------------------------------------------------------| Auto | Manual | IR Selection | | ADR DADS | ADR DADS | | --------------------------------------------------------------------| Open | Open | The IR uses the air data received | | | | on port 1 | |-------------|----------------|-----------------------------------| | Open | Ground | The IR uses the air data received | | | | on port 2 | |-------------|----------------|-----------------------------------| | Ground | Not applicable | The IR goes automatically from one| | | | air data source to the others | | | | according to their validity and | | | | priority. | --------------------------------------------------------------------
Table 4 : ADR DADS Select
R 1EFF : 001-004, 1 34-14-00Page 6 1 1 Config-1 May 01/03 1 1 1CES 1 The A/C is wired in the automatic ADR selection mode with the following priority:
1: its own ADR unit
2: ADR received on port 1
3: ADR received on port 2.
(d) SDI program pins These discretes code the installation side of the ADIRU. The following table gives the IR side according to the SDI.
--------------------------------------------| SDI-MSB | SDI-LSB | ADIRU NUMBER | --------------------------------------------| OPEN | GROUND | 1 | | GROUND | OPEN | 2 | | GROUND | GROUND | 3 | --------------------------------------------
Table 5 : IR SDI Code
(e) Aircraft ident The IR portion uses input discretes to identify the aircraft (type, engine model) on which the ADIRU is installed, and to select the appropriate set of filters for inertial data. To perform this coding, the IR wires seven input discretes and one discrete for parity to a common.
R **ON A/C 001-004,
Post SB 34-1147 For A/C 001-004,
(f)
IR remote test The IR portion uses one discrete to select the remote test by external control. When this discrete is open, the test is not activated. When this discrete is grounded, the test is activated. In normal operation this discrete is open (unused), but can be also activated via the CFDIU (on ground).
(g)
GPS present These discretes are used to activate the GPS/IRS hybridization function (computation, BITE output).
(h)
GPS priority select The GPIRS function uses this discrete to modify the GPS priority. Each ADIRU receives data from the GPS portion of the two MMRs on the primary and secondary inputs.
R 1EFF : 001-004, 1 34-14-00Page 7 1 1 Config-1 May 01/03 1 1 1CES 1 For each ADIRU, the primary and secondary GPS inputs are defined as follows:
----------------------------------------------------------| ADIRU SDI | PRIMARY INPUT | SECONDARY INPUT | |---------------------------------------------------------| 1 | GPS 1 (MMR1) | GPS 2 (MMR2) | | 2 | GPS 2 (MMR2) | GPS 1 (MMR1) | | 3 | GPS 1 (MMR1) | GPS 2 (MMR2) | ----------------------------------------------------------
Depending on the GPS validity and GPS priority select input discrete status, the GPS source is defined as follows:
-------------------------------------------------------------------------------| Priority | Primary | Secondary | GPS source | | Status | GPS | GPS |--------------------------------------| | | | | GPS priority | GPS priority | | | | | select : open | select : GND | -------------------------------------------------------------------------------| 1 | Valid | Valid | Primary | Secondary | | 2 | Valid | Fail | Primary | Primary | | 3 | Fail | Valid | Secondary | Secondary | | 4 | Fail | Fail | Primary | Secondary | -------------------------------------------------------------------------------
R **ON A/C 001-004,
C. Software Computation (Ref. Fig. 001) The software contains the program memory and provides the following basic functions:
-real-time executive
-attitude integration
-velocity integration
-position integration
-GPS/IRS hybridization
- output computation
-built-in test (Ref. 34-18-00).
The IR architecture utilizes two processors:
-DSP C25 for interface with sensors
-INTEL 80960 for I/O and maintenance functions.
The IR software operates in one of three basic modes: alignment,
navigation, or a reversionary attitude mode. These modes include various
portions of the major functions. The real-time executive and built-in
test functions interface with each function in each mode.
R 1EFF : 001-004, 1 34-14-00Page 8 1 1 Config-1 May 01/03 1 1 1CES 1
ADIRU - IR Block Diagram
Figure 001
R 1EFF : 001-004, 1 34-14-00Page 9 1 1 Config-1 May 01/03 1 1 1CES 1 The GPIR function computes a hybrid GPS/IRS solution utilizing inputs received from the IR function and GPSSUs. The GPIR function has two operating modes: GPIR NAV mode and GPIR ATT mode, as indicated by IR mode command. In GPIR NAV mode, all the system state transitions are slaved to the IR function (Align, NAV). 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A320飞机维护手册 AMM NAVIGATION 导航2(20)
