WM8976 Wolfson Microelectronics Ltd., WM8976 Datasheet - Page 74

• Manufacturer Part Number: WM8976
• Description: The WM8976 is a low power, high quality stereo codec designed for portable applications such as Digital still camera or Digital Camcorde
• Manufacturer: Wolfson Microelectronics Ltd.

WM8976
CONTROL INTERFACE
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Table 62 Jack Detect Register Control Bits
SELECTION OF CONTROL MODE AND 2-WIRE MODE ADDRESS
Table 63 Control Interface Mode Selection
The VMID_EN signal has an OR function performed with the normal VMID driver enable. If the
VMID_EN signal is to have no effect to normal functionality when jack detection is enabled, it should
set to 0 for all JD_EN0 or JD_EN1 settings.
If jack detection is not enabled (JD_EN=0), the output enables default to all 1’s, allowing the outputs
to be controlled as normal via the normal output enables found in Table 50.
The control interface can operate as either a 3-wire or 2-wire MPU interface. The MODE pin
determines the 2 or 3 wire mode as shown in Table 63.
The WM8976 is controlled by writing to registers through a serial control interface. A control word
consists of 16 bits. The first 7 bits (B15 to B9) are address bits that select which control register is
accessed. The remaining 9 bits (B8 to B0) are register bits, corresponding to the 9 bits in each
control register.
R9
GPIO control
R13
REGISTER
ADDRESS
MODE
High
Low
5:4
6
8:7
3:0
7:4
BIT
JD_SEL
JD_EN
JD_VMID
JD_EN0
JD_EN1
LABEL
INTERFACE FORMAT
2 wire
3 wire
00
0
00
0000
0000
DEFAULT
Pin selected as jack detection input
00 = GPIO1
01 = GPIO2
10 = GPIO3
11 = Reserved
Jack Detection Enable
0 = disabled
1 = enabled
[7] VMID_EN_0
[8] VMID_EN_1
Output enables when selected jack
detection input is logic 0.
[0]= OUT1_EN_0
[1]= OUT2_EN_0
[2]= OUT3_EN_0
[3]= OUT4_EN_0
Output enables when selected jack
detection input is logic 1
0000-0011 = Reserved
[4]= OUT1_EN_1
[5]= OUT2_EN_1
[6]= OUT3_EN_1
[7]= OUT4_EN_1
DESCRIPTION
PP Rev 3.0 April 2006
Pre-Production
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