wm8770 Wolfson Microelectronics plc, wm8770 Datasheet - Page 25

• Manufacturer Part Number: wm8770
• Description: 24-bit, 192khz 8-channel Codec With Volume Control
• Manufacturer: Wolfson Microelectronics plc

Production Data
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3-WIRE (SPI COMPATIBLE) SERIAL CONTROL MODE
DI is used for the program data, CL is used to clock in the program data and CE is used to latch the
program data. DI is sampled on the rising edge of CL. The 3-wire interface protocol is shown in
Figure 21.
Figure 21 3-wire SPI compatible Interface
CCB INTERFACE MODE
CCB Interface mode allows multiple devices to be controlled off a common 3-wire bus. Each device
on the 3-wire bus has its own identifying address. The WM8770 supports write only CCB interface
mode.
DI is used for the device address and program data and CL is used to clock in the address and data
on DI. DI is sampled on the rising edge of CL. CE indicates whether the data on DI is the device
address or program data. The eight clocks before a rising edge on CE will clock in the device
address. The device address is latched on the rising edge of CE. The sixteen clocks before a falling
edge on CE will clock in the program data. The program data is latched on the falling edge of CE.
Figure 22 CCB Interface – CL stopped low
The address A[7:0] for WM8770 is 8Ch (10001100).
1.
2.
3.
Figure 23 CCB Interface – CL stopped high
1.
2.
3.
DI
CL
CE
CE
CL
DI
CE
CL
DI
B[15:9] are Control Address Bits
B[8:0] are Control Data Bits
CE is edge sensitive – the data is latched on the rising edge of CE.
A[7:0] are Device Address bits
D[15:9] are Control Address bits
D[8:0] are Control Data bits
B15
A0
A0
B14
A1
A1
A2
B13
A2
B12
A3
A3
A4
B11
A4
A5
B10
A5
A6
A6
B9
A7
A7
B8
B7
D0
D0
B6
D1
D1
B5
D2
D2
B4
D3
D3
B3
PD Rev 4.2 March 2008
B2
D14
D14
B1
D15
WM8770
D15
B0
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