2-1.Measures To Prevent Trouble - Casio QT-6600 Installation & Down Recovery Manual

Down Recovery
2-1. Measures to prevent trouble
I-10
The QT-6600 system hardware boasts exceptional reliability. However, no machine can
be completely free from trouble. When a given system can predict a possible trouble or
permits a failing point to spotted easily, the time required for repair can be cut and
consequently, the overall system reliability can be improved.
The QT-6600 system offers a self-diagnostic program for servicemen to enable individual
devices to be checked at the terminal level. For a detailed description of this program, see
the service manual.
If a system error occurred during an actual operation, error informations output to the
terminal display.
Trouble with the terminal CPU can be fatal to the system. In this case, it is impossible even
to obtain an error log. As long as the number of retries is within a predetermined limit, the
processing being performed is not interrupted. By the time the processing is interrupted,
error information is logged, so that the serviceman can repair or replace defective parts
before the system goes down.
To summarize,
1) Terminal-level hardware check:
Self-diagnostic program.
2) Error information, etc. during in / online data transmission:
The error is displayed on the in / online master terminal display and logged in the error
log file.
3) Abnormal completion of processing due to error:
An error message is output to the terminal display.
Needless to say, a backup master is indispensable, since trouble with the master can lead
to system down. In the QT-6600 system, both the master and backup master have the check
tracking system, the files are updated simultaneously (main-mirror system). Thus, even if
either master goes down, the index and detail data remain intact.
And the QT-6600 terminal stores maintenance data in the internal flash memory.
Reading this data by the manager operation (refer to 3-3-22. Maintenance data in the
reference manual) helps troubleshooting.