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Figure 4.19 – EWDM Outer Look
3) Expansion Central Processor Unit(ECPU)
ECPU can inquire and control state of modules to be installed into OEU. This unit
communicates with upper BIU while communicating with lower ROU. It also acts as
communication bridge between BIU and ROU.
In addition, the unit has RS-232C port for serial communication, which enables inquiry and
control of devices thorugh PC. At the front panel, communication LED indicator indicates
communication state with upper BIU and lower ROU. It also has ALM LED indicator to show if a
device gets faulty.
Figure 4.20 – ECPU Outer Look