ALS300 Datasheet, PDF (32/66 Pages) List of Unclassifed Manufacturers – Media Audio Controller SPEC

Avance Logic Inc.
Appendix B : ESP command set
ALS300 only support playback and it‘s related command.
* Undocumented
$ Sound Blaster Pro only
# Sound Blaster 16 only
0Xh reserved
1Xh set audio output mode for 4:1 ADPCM 2 to 8 bit playback
3Xh reserved
4Xh set sample rate and continuos/special DMA block length
5Xh reserved
6Xh reserved
7Xh set audio output for all ADPCM, 8 bit playback
8Xh output silence
9Xh 8 bit special DMA mode playback/record
AXh set MONO/Stereo input mode
BXh 16 bit DMA audio I/O
CXh 8 bit DMA audio I/O
DXh control DMA and speaker
EXh ESP version and diagnostic test
FXh test IRQ and ESP ROM
All 8-bit ESP command is unsigned PCM except CXh command.
All 8-bit ESP command is MONO except command 14h,1Ch,9Xh and CXh
8 Bit And 4:1 ADPCM 2 To 8 Bit Output
1Xh
Bit 3 0
1
direct/normal DMA mode
continuous DMA mode
Bit 2 0
1
direct mode
DMA mode
Bit 1 0
1
8 bit data
4:1 ADPCM 2 to 8 bit mode
Bit 0 0
1
normal
the first ADPCM block with reference byte
10h 8 bit direct mode output
a. ESP_WRITE(10h)
b. ESP_WRITE(single-sample)
c. Wait for next sample time, go to a.
14h 8 bit normal DMA output
a. ESP_WRITE(14h)
b. ESP_WRITE(length.low)
c. ESP_WRITE(lenght.high)
Length = # of byte transfer - 1
ESP will generate an interrupt after the specified size of data transferred.
32
ALS300