The fourth parameter for %DIFF must be a constant between 0 and 12. Defaults to zero.
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Cause . . . . . : The fourth parameter for built-in function %DIFF represents the number of fractional seconds. It must be a constant value between 0 and 12. The parameter is ignored. The number of fractional seconds defaults to zero.
Recovery . . . : Correct the third parameter for built-in function %DIFF. Compile again.