CS4215 Datasheet, PDF (21/52 Pages) Cirrus Logic – 16-Bit Multimedia Audio Codec

CS4215
128 1 2 3 4 64 65 66 67 68 69
SCLK
FSYNC,
TSIN A
TSOUT A,
TSIN B
128 1 2 3 4
TSOUT B
SDIN
Data to A
Data to B
Data to A
SDOUT
_
D/C
Data from A
Data Mode
Data from B
Data from A
Figure 12. Data Mode Timing for 2 CS4215’s
DATA MODE
The data mode is used during conversions to
pass digital data between the CS4215 and exter-
nal devices. The frame sync rate is equal to the
value of the conversion frequency set by the
DFR2-DFR0 bits of the Data Format register.
Each frame has either 64, 128, or 256 bit times
depending on the BSEL bits in the Serial Con-
trol register. Control of gain, attenuation, input
selection and output muting are embedded in the
data stream.
Time slot
1
2
3
4
5
6
7
8
Description
Left Audio MS8 bits
Left Audio LS8 bits
Right Audio MS8 bits
Right Audio LS8 bits
Output Setting
Output Setting
Input Setting
Input Setting
Table 2. Data Registers
Data Formats
+FS
All time slots contain 8 bits. The MSB of the
data is transmitted/received first. The CS4215
data registers have the functions and time slot as-
signments shown in Table 2. The register address
0
is the time slot number when D/C is 1. The
SDOUT pin goes into a high-impedance state
prior to time slot 1 and after Time Slot 8 (see
Figure 12).
The CS4215 supports four audio data formats:
-FS
8-bit
0
unsigned:
65
128
191
255
16-bit 2’s-complement linear, 8-bit unsigned lin-
16-bit
2’s comp:
-32768
-16384
0
16384
32767
ear, 8-bit A-Law, and 8-bit µ-Law. Figure 13
DIGITAL CODE
illustrates the transfer characteristic for 16-bit
and 8-bit linear formats. Note that a digital code
Figure 13. Linear Data Formats
DS76F2
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