Production Data
WM8711BL
3-WIRE (SPI COMPATIBLE) SERIAL CONTROL MODE
The WM8711BL can be controlled using a 3-wire serial interface. SDIN is used for the program data,
SCLK is used to clock in the program data and CSB is used to latch in the program data. The 3-wire
interface protocol is shown in Figure 20.
CSB
SCLK
B15
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
SDIN
Figure 20 3-Wire Serial Interface
Notes:
1.
2.
3.
B[15:9] are Control Address Bits
B[8:0] are Control Data Bits
CSB is edge sensitive not level sensitive. The data is latched on the rising edge of CSB.
2-WIRE SERIAL CONTROL MODE
The WM8711BL supports a 2-wire MPU serial interface. The device operates as a slave device only.
The WM8711BL has one of two slave addresses that are selected by setting the state of the CSB pin.
ACK
ACK
ACK
DATA B15-8
R ADDR
R/W
DATA B7-0
SDIN
SCLK
START
STOP
Figure 21 2-Wire Serial Interface
Notes:
1.
2.
B[15:9] are Control Address Bits
B[8:0] are Control Data Bits
CSB STATE
ADDRESS
0
1
0011010
0011011
Table 18 2-Wire MPU Interface Address Selection
To control the WM8711BL on the 2-wire bus the master control device must initiate a data transfer by
establishing a start condition, defined by a high to low transition on SDIN while SCLK remains high.
This indicates that an address and data transfer will follow. All peripherals on the 2-wire bus respond
to the start condition and shift in the next eight bits (7-bit address + R/W bit). The transfer is MSB first.
The 7-bit address consists of a 6-bit base address + a single programmable bit to select one of two
available addresses for this device (see Table 18). If the correct address is received and the R/W bit
is ‘0’, indicating a write, then the WM8711BL will respond by pulling SDIN low on the next clock pulse
(ACK). The WM8711BL is a write only device and will only respond to the R/W bit indicating a write. If
the address is not recognised the device will return to the idle condition and wait for a new start
condition and valid address.
PD, Rev 4.2, December 2011
3143
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
