FDC37C665GT_07 SMSC [SMSC Corporation], FDC37C665GT_07 Datasheet - Page 112

• Manufacturer Part Number: FDC37C665GT_07
• Description: High-Performance Multi-Mode Parallel Port Super I/O Floppy Disk Controllers
• Manufacturer: SMSC [SMSC Corporation]

Programmed I/O - Transfers from the FIFO to
the Host
In the reverse direction an interrupt occurs when
are available in the FIFO. If at this time the
FIFO is full it can be emptied completely in a
single burst, otherwise readIntrThreshold bytes
may be read from the FIFO in a single burst.
readIntrThreshold =(16-<threshold>) data bytes
An interrupt is generated when serviceIntr is 0
and the number of bytes in the FIFO is greater
than or equal to (16-<threshold>). (If the
threshold = 12, then the interrupt is set
whenever there are 4-16 bytes in the FIFO.) The
PINT pin can be used for interrupt-driven
systems. The host must respond to the request
by reading data from the FIFO. This process is
repeated until the last byte is transferred out of
the FIFO. If at this time the FIFO is full, it can
be completely emptied in a single burst,
otherwise a minimum of (16-<threshold>) bytes
may be read from the FIFO in a single burst.
serviceIntr is 0 and readIntrThreshold bytes
in FIFO
112
Programmed I/O - Transfers from the Host to
the FIFO
In the forward direction an interrupt occurs when
serviceIntr is 0 and there are writeIntrThreshold
or more bytes free in the FIFO. At this time if
the FIFO is empty it can be filled with a single
burst before the empty bit needs to be re-read.
writeIntrThreshold bytes.
writeIntrThreshold = (16-<threshold>)
An interrupt is generated when serviceIntr is 0
and the number of bytes in the FIFO is less than
or equal to <threshold>. (If the threshold = 12,
then the interrupt is set whenever there are 12 or
less bytes of data in the FIFO.) The PINT pin
can be used for interrupt-driven systems. The
host must respond to the request by writing data
to the FIFO. If at this time the FIFO is empty, it
can be completely filled in a single burst,
otherwise a minimum of (16-<threshold>) bytes
may be written to the FIFO in a single burst.
This process is repeated until the last byte is
transferred into the FIFO.
Otherwise
it
may
free bytes in FIFO
be
filled
with