FDC37M607 datasheet(102/182 Pages) SMSC

102 / 182 page

102

the FIFO. If at this time the FIFO is full, it can

completely

emptied

single

burst,

otherwise a minimum of (16-<threshold>) bytes

may be read from the FIFO in a single burst.

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.

Otherwise

may

filled

with

writeIntrThreshold bytes.

writeIntrThreshold =

(16-<threshold>)

free

bytes in FIFO

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.

FDC37M607 Datasheet(PDF) 102 Page - SMSC Corporation