4.2.1.10.2 COMMAND 90H

Function: 8-bit continuous special DMA playback

SB ESP will generate an interrupt after each block length of data has been transferred.

4.2.1.10.3 Command 91h

Function: 8-bit non-continuous special DMA playback

SB ESP will generate an interrupt after the specified block length of data has been transferred.

For non-continuous special DMA playback, every time when SB ESP receives the 91h command, SB ESP will use the block

length that most recently set by command 48h to begin the special DMA transfer.

4.2.1.10.4 Command 98h

Function: 8-bit continuous special DMA recording

SB ESP will generate an interrupt after the specified block length of data has been transferred.

4.2.1.10.5 Command 99h

Function: 8-bit non-continuous special DMA recording

SB ESP will generate an interrupt after the specified block length of data has been transferred.

4.2.1.11 16-Bit Audio Playback/Recording Command Bxh

4.2.1.11.1 Command Bit Definition

Bit 3

0 Playback

1 Recording

Bit 2

0 Non-Continuous DMA

1 Continuous DMA

Bit 1 X Reserved

Bit 0 X Reserved

4.2.1.11.2 Command B0h/B1h/B2h/B3h/B4h/B5h/B6h/B7h

Function: 16-bit audio playback

Mode

Bit 7..6 X reserved

Bit 5

0 mono

1 stereo

Bit 4

0 unsigned PCM (0–8000h–FFFFh)

1 signed PCM (8000h–0–7FFFh)

Bit 3..0 X reserved

Length = number of words to be transferred -1

For non-continuous DMA, SB ESP will generate an interrupt and terminate the DMA transfer after the specified length of data has

been transferred.

For continuous DMA, SB ESP will generate an interrupt after each specified block length of data has been transferred.

4.2.1.11.3 Command B8h/B9h/BAh/BBh/BCh/BDh/BEh/BFh

Function: 16-bit audio recording

Mode

Bit 7..6 X reserved

Bit 5

0 mono

1 stereo

Bit 4

0 unsigned PCM (0–8000h–FFFFh)

1 signed PCM (8000h–0–7FFFh)

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