Campbell CR6 Series, Руководство оператора

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Section 11. Glossary
584
memory is configured as ring memory
(p. 598)
by default, with new data
overwriting the oldest data.
Term: final-storage data
Data that resides in final-data memory.
Term: Flash
A type of memory media that does not require battery backup. Flash memory,
however, has a lifetime based on the number of writes to it. The more
frequently data are written, the shorter the life expectancy.
Term: FLOAT
Four-byte floating-point data type. Default CR6 data type for Public or Dim
variables. Same format as IEEE4.
Term: fN1
fN1, F notch, or first-notch frequency
(p. 421).
A digital filter. A notch, when
referring to digital signal processing (DSP), is a region in the frequency
response at which frequencies input into the filter are highly attenuated or
'notched out.' Signals input into the filter at fN1 are completely eliminated,
whereas frequencies near the notch are greatly attenuated but not completely
filtered out. A more technical term is
transmission zero
,or zero signal
transmission through the filter at the given frequency.
A less technical description is that the fN1 value can be thought of as the
reciprocal of the integration time. The smaller the fN1, the longer the
integration of the signal. For example, an fN1 of 50 is equivalent to a 20 ms
integration, which is the exact time required in integrate a signal over the
length of 50 Hz ac mains noise that may be a noise frequency in the signal,
effectively filtering out the 50 Hz noise.
Term: FP2
Two-byte floating-point data type. Default CR6 data type for stored data.
While IEEE four-byte floating point is used for variables and internal
calculations, FP2 is adequate for most stored data. FP2 provides three or four
significant digits of resolution, and requires half the memory as IEEE4.
Term: FTP
File Transfer Protocol. A TCP/IP application protocol.