Sony GY-2120WD Maintenance Manual page 245

IF CPU Block Check
a) ROM Check (Self-diagnosis command No. 52)
Enter "52" as a command number and press the ENTER key.
The sum of ROMs in a IF CPU block is checked automatically.
DIAGNOSTIC=>52
-------[ IF CPU ROM Check ]-------
Start OK
DIAGNOSTIC=>_
In case that the check succeeds;
Message "OK" is displayed.
In case that the check fails;
Message "ERROR!!" is displayed.
In this case, stop the GY-2120 operation immediately. Moreover, replace the IF-682/683 board
which mounts the ROM.
b) RAM Check (Self-diagnosis command No. 53)
Enter "53" as a command number and press the ENTER key.
The work memory of the IF CPU is checked automatically.
DIAGNOSTIC=>53
-------[ IF CPU RAM Check ]-------
Start OK
DIAGNOSTIC=>_
In case that the check succeeds;
Message "OK" is displayed.
In case that the check fails;
Message "ERROR!!(error count:xxxxxxxx)" is displayed.
"xxxxxxxx" indicates the number of error words.
GY-2120WD/WS
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6-2. Command Description
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