WM8912
Production Data
GENERAL PURPOSE INPUT/OUTPUT (GPIO)
The WM8912 provides two multi-function pins which can be configured to provide a number of
different functions. These are digital input/output pins on the DBVDD power domain. The GPIO pins
are:
•
•
IRQ/GPIO1
BCLK/GPIO4
Each general purpose I/O pin can be configured to be a GPIO input or configured as one of a
number of output functions. Signal de-bouncing can be selected on GPIO input pins for use with
jack/button detect applications. Table 51 lists the functions that are available on each of the GPIO
pins.
GPIO PIN FUNCTION
GPIO PINS
IRQ / GPIO1
BCLK / GPIO4
GPIO input
Yes
Yes
(including jack/button detect)
GPIO output
Yes
No
Yes
Yes
Yes
Yes
Yes
BCLK
Interrupt (IRQ)
Yes
Yes
Yes
FLL Lock output
FLL Clock output
Table 51 GPIO Functions
IRQ/GPIO1
The IRQ/GPIO1 pin is configured using the register bits described in Table 52. By default, this pin is
IRQ output with pull-down resistor enabled.
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
5
GPIO1_PU
0
GPIO1 pull-up resistor enable
0 = pull-up disabled
R121 (79h)
GPIO
1 = pull-up enabled
Control 1
4
GPIO1_PD
1
GPIO1 pull-down resistor enable
0 = pull-down disabled
1 = pull-down enabled
GPIO1 Function Select
0000 = GPIO input
3:0
GPIO1_SEL [3:0]
0100
0001 = Clock output
(f=SYSCLK/OPCLKDIV)
0010 = Logic '0' output
0011 = Logic '1' output
0100 = IRQ output (default)
0101 = FLL Lock output
0110 = Reserved
0111 = Reserved
1000 = Reserved
1001 = FLL Clock output
1010 to 1111 = Reserved
Table 52 IRQ/GPIO1 Control
PD, Rev 4.0, September 2010
76
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
