1 transmit fifo service (tfs) – Intel PXA26X User Manual
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Intel® PXA26x Processor Family Developer’s Manual
Universal Serial Bus Device Controller
12.6.3
UDC Endpoint x Control/Status Register (UDCCSx), Where
x is 1, 6, or 11
The UDC Endpoint(x) Control Status Register contains 6 bits operate endpoint(x), a bulk IN
endpoint).
12.6.3.1
Transmit FIFO Service (TFS)
The transmit FIFO service bit is active if one or fewer data packets remain in the transmit FIFO.
TFS is cleared when two complete packets of data remain in the FIFO. A complete packet of data is
signified by loading 64 bytes of data or by setting UDCCSx[TSP].
Table 12-13. UDC Endpoint 0 Control Status Register
0h 4060 0010
UDCCS0
Read/Write
Bit
31:8
7
6
5
4
3
2
1
0
Reserved
SA
RNE
FST
SST
DRWF
FTF
IPR
OPR
Rese
t
X
0
0
0
0
0
0
0
0
Bits
Name
Description
0
OPR
OUT PACKET READY (read/write 1 to clear):
1 – OUT packet ready.
1
IPR
IN PACKET READY (always read 0/write 1 to set):
1 – IN packet ready.
2
FTF
FLUSH Tx FIFO (always read 0/write 1 to set):
1 – Flush the contents of Tx FIFO.
3
DRWF
DEVICE REMOTE WAKE UP FEATURE (read-only):
0 – Device remote wake up feature is disabled.
1 – Device remote wake up feature is enabled.
4
SST
SENT STALL (read/write 1 to clear):
1 – UDC sent stall handshake
5
FST
FORCE STALL (read/write 1 to set):
1 – Force stall handshake
6
RNE
RECEIVE FIFO NOT EMPTY (read-only):
0 – Receive FIFO empty.
1 – Receive FIFO not empty.
7
SA
SETUP ACTIVE (read/write 1 to clear):
1 – Setup command is active on the USB
31:8
—
Reserved for future use