(2) Display Management Computers (DMC) The 3 DMCs are identical. Each integrates the EFIS/ECAM functions, and is able to drive simultaneously one PFD, one ND, and either ECAM display unit. The DMCs acquire and process all the signals received from various A/C sensors and computers. This in order to generate proper codes of graphic instructions corresponding to the images to be displayed. These codes are sent in digital form, using a very high speed (800 kbauds) RZ type transmission, through a twisted shielded pair of wires, called Dedicated Serial Data Link (DSDL). The DMC comprises four parts:
 -acquisition
 -PFD channel

 -ND channel

 -ECAM channel.
 The acquisition module enables the DMC to acquire all input signals
 such as:

 -discretes

 -
ARINC 429

 -
ARINC 453 for weather radar image

 -dedicated FWC link (RS-422).

 1EFF : 106-149, 303-399, 1 31-60-00Page 18 1 1 Config-3 Aug 01/05 1 1 1CES 1 The three channels enable the DMC to process simultaneously data for three different images: PFD, ND, and upper or lower ECAM Display Unit. Each channel ensures data management and processing. This in order to elaborate the instructions for drawing the images which are required according to the pilot controls/selections and the A/C status/ configuration. The operational programs corresponding to each channel is loaded into memory modules, slipped in their respective slots through the DMC dog house face. This design has been chosen so as to facilitate the independent reprogramming of the DMC. The weather radar processing is made separately, by a dedicated board. The weather radar information that enters the DMC through ARINC 453 very high speed data buses is converted into X, Y and color data. Then this information is sent to the EFIS DUs via 4 digital buses, 3 for color and one for synchro.

 (a) Safety aspects Since some parameters displayed by the EIS are flight essential or flight critical, the DMC hardware and software are designed to cope with the specified safety requirements. Considering this safety aspect, the three channels are independent and each of them takes the data needed for computation in dedicated memory area. These data are protected against inadvertent access from the other channels. Architecture and software monitoring precautions are taken in order to cope with the classification of the software, particularly with respect to the processing of flight critical data. For example a comparison is performed between:
 -the pitch and roll data received and processed by the DMC on one hand
 -and the pitch and roll feedback signal received from the PFD and which stand for the displayed pitch and roll information, on the other hand.
 (Ref. Fig. 010)
 Moreover, the FWC performs an extra comparison between:

 -the pitch (and roll as well) information displayed on Captain's PFD
 -and the pitch (and roll) data delivered by the IRS2, and
 likewise between the First Officer's PFD and IRS1 data. Inside the DMC, the monitoring for the baro altitude and for the engine primary parameters is similar: it also performs a comparison between the displayed information and the input parameters.
 1EFF : 106-149, 303-399, 1 31-60-00Page 19 1 1 Config-3 Aug 01/05 1 1 1CES 1

 DMC Output Bus - Attitude Comparison on CAPT and F/O PFDs
 Figure 010

 1EFF : 106-149, 303-399, 1 31-60-00Page 20 1 1 Config-3 Aug 01/05 1 1 1CES 1 Inside the FWC, the comparison performed for the heading indications is simple: comparison between the heading parameters used for display on side 1 and side 2.

 (3)
 EFIS Control (Ref. Fig. 011, 012) EFIS control sections The EFIS control sections of the FCU, which are situated on either side of the FCU and are part of it, allow the pilot to select desired modes and data on his PFD and ND:

 -ND mode (ROSE, MAP...)
 -geographic scale marks range
 - options for complementary information on the map

 -trajectory deviation mode (VOR, NAV, ILS)
 -guidance mode ON or OFF (Flight Director bars or Flight Path Director)
 -altitude reference selection (baro setting).

 (4)
 ECAM Controls (Ref. Fig. 005, 013)

 (a) ECAM control panel The ECAM control panel (ECP) allows the selection of the display on the ECAM DUs as far as the A/C system/status images are concerned. The ECAM control panel enables:
 -manual selection of any A/C system diagram
 -sequential display of all the A/C system pages by means of the ALL key.
 (b) Transfer pushbutton switches Several types of manual transfer will be left at the disposal of the pilots:
 -EIS DMC transfer, CAPT/3 or F/O/3, for EFIS and ECAM (DMC 3 taking over in case of DMC 1 or DMC 2 failure)
　
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