Description
Reset
Type
Name
Bit/Field
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0x0
RO
reserved
23:22
Transmit Store and Forward
Description
Value
Transmission starts according to
TTC
bit field.
0
Transmission starts when a full frame resides in the TX/RX
Controller Transmit FIFO. Additionally, the
TTC
values specified
in
TTC
bits[16:14] are ignored. This bit should be changed only
when the transmission is stopped.
1
0x0
RW
TSF
21
Flush Transmit FIFO
This bit is cleared internally when the flushing operation is completed.
This register should not be written to until the
FTF
bit is cleared. The
data which has already been accepted by the MAC transmitter is not
flushed. It is scheduled for transmission and results in underflow and
runt frame transmission.
Description
Value
This bit indicated normal operation or that the flushing operation
has completed.
0
The transmit FIFO controller logic is reset to its default values
and thus all data in the TX FIFO is lost or flushed.
This bit is cleared internally when the flushing operation is
complete.
1
Note:
The flush operation is complete only when the TX FIFO is
emptied of its contents and all the pending Transmit Status
of the transmitted frames are accepted by the host.
0x0
RW
FTF
20
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0x0
RO
reserved
19:17
Transmit Threshold Control
These bits control the threshold level of the TX/RX Controller Transmit
FIFO. Transmission starts when the frame size within the TX/RX
Controller Transmit FIFO is larger than the threshold. In addition, full
frames with a length less than the threshold are also transmitted. These
bits are used only when Bit 21 (
TSF
) is reset.
Description
Value
64 bytes
0x0
128 bytes
0x1
192 bytes
0x2
256 bytes
0x3
40 bytes
0x4
32 bytes
0x5
24 bytes
0x6
16 bytes
0x7
0x0
RW
TTC
16:14
June 18, 2014
1568
Texas Instruments-Production Data
Ethernet Controller