21 I
2
S
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
21-17
7.5 Sample Clock Settings
Table 21.
WSCLKCYC[4:0]
Sample clock period
(number of bit clock cycles)
0x1f–0x11
Reserved
0x10
32 clocks
0xf
31 clocks
0xe
30 clocks
0xd
29 clocks
0xc
28 clocks
0xb
27 clocks
0xa
26 clocks
0x9
25 clocks
0x8
24 clocks
0x7
23 clocks
0x6
22 clocks
0x5
21 clocks
0x4
20 clocks
0x3
19 clocks
0x2
18 clocks
0x1
17 clocks
0x0
16 clocks
(Default: 0x0)
The sampling clock frequency is calculated as below.
f
I2S_SCLK
f
S
= ———— [Hz]
n
×
2
f
S
:
Sampling clock frequency [Hz]
f
I2S_SCLK
: Bit clock frequency [Hz] (See Table 21.7.6.)
n:
Number of bit clocks selected by WSCLKCYC[4:0] (See Table 21.7.5.)
Note: The value to be set to the WSCLKCYC[4:0] is not the number of audio data bits, but the num-
ber of bit clock cycles that is used to adjust the sample clock period. It must be equal to or
greater than the number of audio data bits (16 bits).
1
2
3
15
16
17
n
1
2
3
D15
D2
D1
D0
D14
I2S_WS
I2S_SCLK
Bit clock cycle count
(by setting WSCLKCYC[4:0])
I2S_SDO
(L channel)
(R channel)
(MSB first, I
2
S mode)
D2
D15 D14
7.8 Sample Clock Period
Figure 21.
D[7:0]
BCLKDIV[7:0]: I
2
S Bit Clock Division ratio Select Bits
Configures the bit clock to be output.
The I
2
S module generates the bit clock to be output from the I2S_SCLK pin of the I
2
S by dividing
PCLK1. Specify the division ratio using BCLKDIV[7:0].
7.6 I2S_SCLK (Bit Clock) Settings
Table 21.
BCLKDIV[7:0]
PCLK1 division ratio
0xff
1/512
0xfe
1/510
0xfd
1/508
:
:
0x2
1/6
0x1
1/4
0x0
1/2
(Default: 0x0)