ALS300 Datasheet, PDF (37/66 Pages) List of Unclassifed Manufacturers – Media Audio Controller SPEC

Avance Logic Inc.
ALS300
command. When CR0.2 is 0, ESP will continue DMA transfer after the interrupt is acknowledged,
this is SB16 90h command.
$91h 8 bit non-continuous special DMA output
ESP_WRITE(91h)
ESP will generate an interrupt after the specified size of data transferred.
For non-continuous special DMA output, every time when ESP receives the 91h command, ESP
will use the block length that most recently set by command 48h to begin the special DMA
transfer. So if every block of DMA data is the same size, software needs only set block length one
time by using command 48h. When each block is transfered over, software needs only send 91h
command to ESP, the DMA transfer will then continue with previous block length.
16 Bit DMA Audio I/O
#BXh
Bit 3
0
audio output (Bit 3 should be “0” in ALS300)
1
audio input
Bit 2
0
non-continuous DMA
1
continuous DMA
Bit 1
X
reserved
Bit 0
X
reserved
FIFO will reset when ESP receives any digital audio I/O command.
FIFO is always on.
a. ESP_WRITE(BXh)
b. ESP_WRITE(mode)
c. ESP_WRITE(length.low)
d. ESP_WRITE(length.high)
Mode
Bit 7 X
Bit 6 X
Bit 5 0
1
Bit 4 0
1
Bit 3 X
Bit 2 X
Bit 1 X
Bit 0 X
reserved
reserved
MONO
stereo
unsigned (0--8000h--FFFFh)
signed (8000h--0--7FFFh)
reserved
reserved
reserved
reserved
Length = # of 16 bit sample -1
ESP will generate an interrupt after the specified size of data transferred (if non-continuous) or every
block(if continuous).
8 Bit DMA Audio I/O
#CXh
Bit 3 0
1
Bit 2 0
1
Bit 1 X
audio output (Bit 3 should be “0” in ALS300)
audio input
non-continuous DMA
continuous DMA
reserved
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