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(i) Messages - Non-volatile Memory
1) Certain status/maintenance and maintenance messages are stored in non-volatile memory (NVM). These messages will still be displayed even after the condition generating them no longer exists.
2) Maintenance messages displayed when the ECS/MSG auto-event page is selected are those that are stored in NVM. They are also displayed in the real time list of status or maintenance messages, as applicable. ECS/MSG messages stored NVM can only be erased when the ECS/MSG Auto Event page is displayed.
(8) EICAS Messages
(a) A complete list of EICAS Messages is in FIM EICAS MESSAGE LIST.
3. Operation (Fig. 6)_________
A. Functional Description
(1)
The EICAS maintenance panel and caution CANCEL/RECALL switches provide signals to the display select panel. The display select panel then provides all control signals through data buses to the EICAS computers.
(2)
The internal operation of the left and right computers is similar therefore, only the left computer is shown. The input functions of the computer can be divided into the following:
(a)
Power up routines
(b)
Digital data bus receivers.
(c)
Analog signal conditioning and multiplexing.
(d)
Warning, caution, and advisory message discrete logic and display.
(e)
Status and maintenance message discrete logic and display.
(3)
The computer assembles data from all its inputs into display formats. It then provides outputs to the display switching modules, caution and warning system, the other EICAS computer, and other airplane systems.
(4)
The display switching modules route video driving signals from the left or right computer to the EICAS display units for display.
(5)
EICAS Power (Fig. 7)
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LEFT SHOWN, RIGHT EQUIVALENT TO/FROM RIGHT SYSTEM
EICAS Computer Schematic Figure 6 (Sheet 1)
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LEFT EICAS COMPUTER
EICAS Computer SchematicFigure 6 (Sheet 2)
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H07593 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：757 AMM 飞机维护手册 仪表 CHAPTER 31 - INSTRUMENTS 2(28)
