SAA7785 Datasheet, PDF (46/68 Pages) NXP Semiconductors – ThunderBird Avenger PCI Audio Accelerator

Philips Semiconductors
ThunderBird Avenger^TM PCI Audio
Accelerator
Preliminary Specification
SAA7785
Bit
5:4
Name
DMAABASE
3
R
2:1 XFRSIZ
0
DDMAAEN
R/W
Function
RW DMA channel A programmable base address, bits 5:4. These bits select a
channel number for this channel. In LAM DMAABASE[5:4] select the channel
number that this DMA represents, it should be different than DMAB-
BASE[5:4].
RO Reserved. This bit must always be zero.
RW DMA transfer size.
00 = reserved
10 = double word
11 = reserved
01 = reserved
RW DDMA channel A enable. This DDMA channel is enabled when this bit is set
to a one.
TABLE 31 DMA Channel B Base Address Register - DMABBASE (RW)
PCI CFG 0
D31
D30
D29
D28
D27
D26
D25
D24
Offset 42h
DMABBASE[15:8]
POR Value
0
0
0
0
0
0
0
0
D23
D22
D21
D20
D19
D18
D17
D16
DMAB
R
DMABBASE[5:4]
R
R
R
DDMAB
BASE[7]
EN
POR Value
0
0
0
0
0
0
0
0
Bit
15:7
Name
DMABBASE
6
R
5:4 DMABBASE
3:1 R
0
DDMABEN
R/W
Function
RW DMA channel B programmable base address. Normally this base is set the
same as DMA channel A except for DMABBASE[5:4] which select the chan-
nel number. This is a requirement of some PC chipsets, future chipsets may
eliminate this requirement. In LAM DMABBASE[5:4] select the channel num-
ber that this DMA represents, it should be different than DMAABASE[5:4].
RO Reserved. This bit must always be zero.
RW DMA channel B programmable base address, bits 5:4. These bits select a
channel number for this channel. In LAM DMABBASE[5:4] select the channel
number that this DMA represents, it should be different than DMAA-
BASE[5:4].
RO Reserved. These bits must always be zeros.
RW DMA channel B enable. This DDMA channel is enabled when this bit is set to
a one.
1999 Nov 12
46