Description
Reset
Type
Name
Bit/Field
Address Aligned Beats
Description
Value
Address aligned transfers are not enabled.
0x0
If the
FB
bit is set, the internal bus interface generates all bursts
aligned to the start address least significant bits.
If the
FB
bit is 0, the first burst is not aligned but subsequent
bursts are aligned to the address.
0x1
0
RW
AAL
25
8 x Programmable Burst Length (PBL) Mode
Description
Value
8 x PBL mode is inactive.
0x0
Bit field
RPBL
and bit field
PBL
are multiplied 8 times. Therefore,
the DMA transfers the data in bursts of 8, 16, 32, 64, 128, and
256 words.
0x1
0
RW
8xPBL
24
Use Separate Programmable Burst Length (PBL)
Description
Value
The
PBL
value in bits[13:8] is applicable for both the RX and
TX DMA engines.
0x0
RX DMA is uses the
RPBL
bit field as its defined programmable
burst length and TX DMA uses the
PBL
bit field as its defined
programmable burst length.
0x1
0
RW
USP
23
RX DMA Programmable Burst Length (PBL)
When the
USP
bit is 1, this field is used to indicate the maximum number
of words to be transferred in one RX DMA transaction. This is the
maximum value that is used in a single block read or write.
The RX DMA always attempts to burst as specified in the
RPBL
bit each
time it starts a burst transfer on the system bus. The application can
program
RPBL
with values of 1, 2, 4, 8, 16, and 32. Any other value
results in undefined behavior. This field is valid and applicable only when
USP
is set high.
0x1
RW
RPBL
22:17
Fixed Burst
This bit defines if burst is used during burs transfer operations.
Description
Value
The DMA bursts the entire length during burst transfers except
for the last word, which is a single transfer.
0x0
The DMA uses only single, or fixed bursts incremented by 4, 8,
or 16 during normal bus transfers.
0x1
0
RW
FB
16
June 18, 2014
1554
Texas Instruments-Production Data
Ethernet Controller