EMAC Registers
1014
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Ethernet Controller
15.6.54 EMACDMABUSMOD Register (Offset = 0xC00) [reset = 0x00020101]
Ethernet MAC DMA Bus Mode (EMACDMABUSMOD)
The Ethernet MAC DMA Bus Mode (EMACDMABUSMODE) register establishes the operation modes for
the DMA.
EMACDMABUSMOD is shown in
and described in
Return to
Figure 15-69. EMACDMABUSMOD Register
31
30
29
28
27
26
25
24
RIB
RESERVED
TXPR
MB
AAL
8xPBL
R/W-0x0
R-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x0
23
22
21
20
19
18
17
16
USP
RPBL
FB
R/W-0x0
R/W-0x1
R/W-0x0
15
14
13
12
11
10
9
8
PR
PBL
R/W-0x0
R/W-0x1
7
6
5
4
3
2
1
0
ATDS
DSL
DA
SWR
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x1
Table 15-79. EMACDMABUSMOD Register Field Descriptions
Bit
Field
Type
Reset
Description
31
RIB
R/W
0x0
Rebuild Burst.
0x0 = During a retry, split or loss of bus, the DMA rebuilds the
pending beats of any burst transfer with a continuous, uninterrupted
burst until the last word, which is a single burst.
0x1 = During a retry, split or loss of bus, the DMA rebuilds the
pending beats of any burst transfer initiated with a defined fixed
burst of 1, 4, 8, or 16.
30-28
RESERVED
R
0x0
27
TXPR
R/W
0x0
Transmit Priority.
0x0 = The RX DMA has higher priority than the TX DMA during
arbitration for the system bus.
0x1 = The TX DMA has higher priority than the RX DMA during
arbitration for the system bus.
26
MB
R/W
0x0
Mixed Burst.
0x0 = Mixed burst is not enabled.
0x1 = If the FB bit is 0, the DMA starts all bursts of length more than
16 with a continuous undefined burst.For bursts less than 16, fixed
and single bursts are used.
25
AAL
R/W
0x0
Address Aligned Beats.
0x0 = Address aligned transfers are not enabled.
0x1 = 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.
24
8xPBL
R/W
0x0
8 x Programmable Burst Length (PBL) Mode.
0x0 = 8 x PBL mode is inactive.
0x1 = 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.