TITLE COLOR DESCRIPTION**
MU Pass Green CMU Working
HW FAIL Red Detected condition which requires box removal
LOAD SW Yellow MU requires loading SW
XFER BUSY Yellow MU data load in progress or using PCMCIA card
XFER COMP Green MU has completed loading
XFER FAIL Red MU has detected failure during load process
APM FAIL Red MU detected failure in APM mode
When CMU first powers up, all the LED(s) on the front panel should light up for a short period of time. After that point the CMU should always have at least one LED illuminated.
MU PASS : The MU PASS LED should be illuminated whenever the CMU is working and has detected no faults which require the
CMU box to be serviced.
HW FAIL : The HW FAIL LED shall be illuminated whenever the CMU detects a hardware failure which requires the CMU box to
be returned to the shop for maintenance. The type of faults include RAM test failures and other HW tests which have failed. This
LED is also illuminated if the hardware part number has not been stored in the CMU (this should be done during an ATP). Before
removing the unit, it is recommended that the data loading of software be performed to see if the loading of software resolves this
problem.
LOAD SW : The LOAD SW LED shall be illuminated whenever the CMU detects a condition which could be fixed, if the correct
SW is loaded. This type of fault includes things like if there is a database mismatch or if there is a compatibility problem between SW
partitions. Also, this LED will be illuminated if the BITE SW detects a Cyclical Redundancy Check error in one of the software
partitions.
XFER BUSY: The XFER BUSY LED shall blink whenever the CMU is performing a data load from either a Data Loader or from the
PCMCIA card. The LED shall be on steady whenever the CMU is using the PCMCIA card for a purpose other than a data load.
XFER COMP : The XFER COMP LED shall be illuminated after the CMU has successfully performed a load operation. The XFER
COMP LED shall be turned off when the PCMCIA card is removed or when the Data Loader discrete becomes inactive.
*** Always make sure this green LED is illuminated before disconnecting the Data Loader Cable from CMU during software
installation ***
XFER FAIL: The XFER FAIL LED shall be illuminated if the CMU is unsuccessful in performing a load operation. This includes
any errors which prevent the CMU from completing the load operation. The XFER COMP LED shall remain on until a load operation
is initiated.
APM FAIL: The APM FAIL LED shall be illuminated if the CMU detects a failure in the APM module. APM FAIL LED will only
be illuminated in CMU configurations which required the APM module for correct operation. This LED is currently not used.
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本文链接地址：MARK II COMMUNICATIONS MANAGEMENT UNIT (CMU) 通讯管理装置 LINE MAINTENANCE GUIDE 航线维护指南(2)
