Buffer descriptor pointer register, Dma channel 1/2 control register – Digi NS9750 User Manual
Page 515

w w w . d i g i e m b e d d e d . c o m
4 9 1
B B u s B r i d g e
Buffer Descriptor Pointer register
Address: A040 0000 / 0020
This register contains a 32-bit pointer to the first buffer descriptor in a contiguous list
of buffer descriptors. The BBus bridge contains a Buffer Descriptor Pointer register
for each DMA channel; each register is 16 bytes in length.
Register bit assignment
DMA Channel 1/2 Control register
Address: A040 0004 / 0024
This register contains required DMA transfer control information. The BBus bridge
contains a DMA Channel Control register for each channel.
Bit(s)
Access
Mnemonic
Reset
Description
D31:00
RW
BuffDesc
0x00000000
Buffer descriptor
32-bit pointer to a buffer descriptor.
Table 296: Buffer Descriptor Pointer register bit definition
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
BuffDesc
BuffDesc
INDEX
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
Reserved
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
CG
SB
DB
SINC_N DINC_N
CE
CA
Not used
SW
DW