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SUDFIFO
Meaning:
Setup Data FIFO
.
Location:
SUDFIFO[7:0]
Write:
When the SIE receives a CONTROL transfer from the host, it copies the eight
SETUP data bytes into this FIFO. When the bytes are verified to be error-free, the
SIE asserts the Setup Data Available Interrupt Request (page 66).
Read:
The CPU does eight reads to this register to retrieve the eight SETUP bytes.
POR:
SUDFIFO=0
Chip Reset:
SUDFIFO=0
Bus Reset:
SUDFIFO=0
Pwr Down:
No read or write
Programming Notes:
The MAX3420E provides this separate FIFO to avoid mixing data and command bytes in the
EP0FIFO (page 10). This relieves the programmer of the task of figuring out the type of data in
the FIFO—the EP0FIFO (page 10) always contains data, and the SUDFIFO always contains
commands.
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