Keithley KPCMCIA-12AIAOH, Руководство пользователя

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KPCMCIA-12AIAOH User’s Manual I/O Registers C-5
FIFO flags
When reading the register under mode 1 or 3, the first available data byte from the data FIFO will
be returned if it is not empty. Otherwise, the returned byte is not defined. The FIFO empty flag
will be set immediately after the last byte is read from the FIFO, while the FIFO full flag will be
cleared after reading the data FIFO register provided no more data bytes are written into the FIFO
by the A/D converter under mode 1 or 3. The same happens to the FIFO almost full flag, if the
data bytes available in the FIFO are less than the almost full threshold. Refer to Table C-5.
Table C-5
Data FIFO flag status
Data bytes in FIFO Empty Almost full Full
0 True False False
1 to (Threshold - 1) False False False
Threshold to (FIFO size - 1) False True False
FIFO size (4096 bytes*) False True True
*Note: Threshold is the almost-full threshold, and FIFO size is measured in bytes,
4096 (2048 samples/data words).