CS47L85 datasheet(328/370 Pages) CIRRUS

328 / 370 page

CS47L85

328

Rev 4.3

AUTOMATIC SAMPLE RATE DETECTION SEQUENCES

The CS47L85 supports automatic sample rate detection on the digital audio interfaces (AIF1, AIF2, AIF3 and AIF4), when

operating in AIF Slave mode. Automatic sample rate detection is enabled using the RATE_EST_ENA register bit (see Table

105).

Up to four audio sample rates can be configured for automatic detection; these sample rates are selected using the

SAMPLE_RATE_DETECT_n registers. If one of the selected audio sample rates is detected, then the Control Write

Sequencer will be triggered. The applicable start index location within the sequencer memory is separately configurable for

each detected sample rate.

The WSEQ_SAMPLE_RATE_DETECT_A_INDEX register defines the sequencer start index corresponding to the

SAMPLE_RATE_DETECT_A sample rate. Equivalent start index values are defined for the other sample rates, as described

in Table 120.

Note that a sequencer start index of 1FFh will cause the respective sequence to be aborted.

The automatic sample rate detection control sequences are undefined following Power-On Reset (POR), Hardware Reset,

or following a Sleep mode transition. The automatic sample rate detection control sequences must be reconfigured by the

host processor following any of these events. Note that all control sequences are maintained in the sequencer memory

through Software Reset.

See “Clocking and Sample Rates” for further details of the automatic sample rate detection function.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R97

(0061h)

Sample_Rat

e_Sequenc

e_Select_1

8:0

WSEQ_SAMPLE

_RATE_DETECT

_A_INDEX [8:0]

1FFh

Sample Rate A Write Sequence start

index

This field contains the index location in

the sequencer memory of the first

command in the sequence associated

with Sample Rate A detection.

Valid from 0 to 507 (1FBh).

R98

(0062h)

Sample_Rat

e_Sequenc

e_Select_2

8:0

WSEQ_SAMPLE

_RATE_DETECT

_B_INDEX [8:0]

1FFh

Sample Rate B Write Sequence start

index

This field contains the index location in

the sequencer memory of the first

command in the sequence associated

with Sample Rate B detection.

Valid from 0 to 507 (1FBh).

R99

(0063h)

Sample_Rat

e_Sequenc

e_Select_3

8:0

WSEQ_SAMPLE

_RATE_DETECT

_C_INDEX [8:0]

1FFh

Sample Rate C Write Sequence start

index

This field contains the index location in

the sequencer memory of the first

command in the sequence associated

with Sample Rate C detection.

Valid from 0 to 507 (1FBh).

R100

(0064h)

Sample_Rat

e_Sequenc

e_Select_4

8:0

WSEQ_SAMPLE

_RATE_DETECT

_D_INDEX [8:0]

1FFh

Sample Rate D Write Sequence start

index

This field contains the index location in

the sequencer memory of the first

command in the sequence associated

with Sample Rate D detection.

Valid from 0 to 507 (1FBh).

Table 120 Write Sequencer Control - Automatic Sample Rate Detection

CS47L85 Datasheet(PDF) 328 Page - Cirrus Logic

CS47L85 Datasheet(HTML) 328 Page - Cirrus Logic

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL