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.

4.2.1.12 8-Bit Audio Playback/Recording Command Cxh

4.2.1.12.1 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

4.2.1.12.2 Command C0h/C1h/C2h/C3h/C4h/C5h/C6h/C7h

Function: 8-bit audio playback

Procedure:

1.

SB ESP_Write(C0h/C1h/C2h/C3h/C4h/C5h/C6h/C7h)

2.

SB ESP_Write(Mode)

3.

SB ESP_Write(Length.low)

4.

SB ESP_Write(Length.high)

Mode

Bit 7..6 X reserved

Bit 5

0 mono

1 stereo

Bit 4

0 unsigned PCM (0–80h–FFh)

1 signed PCM (80h–0–7Fh)

Bit 3..0 X reserved

Length = number of bytes 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.

4.2.1.12.3 Command C8h/C9h/CAh/CBh/CCh/CDh/CEh/CFh

Function: 8-bit audio recording

Mode

Bit 7..6 X reserved

Bit 5

0 mono

1 stereo

Bit 4

0 unsigned PCM (0–80h–FFh)

1 signed PCM (80h–0–7FFh)

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.

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