wm8918 Wolfson Microelectronics plc, wm8918 Datasheet - Page 106

• Manufacturer Part Number: wm8918
• Description: Ultra Low Power Dac For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

WM8918
GENERAL PURPOSE INPUT/OUTPUT (GPIO)
w
R121 (79h)
GPIO
Control 1
The WM8918 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:
•
•
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 69 lists the functions that are available on each of the GPIO
pins.
GPIO Pin Function
GPIO input
(including jack/button detect)
GPIO output
BCLK
Interrupt (IRQ)
MICBIAS current detect
MICBIAS short-circuit detect
Digital microphone interface
(DMIC clock output)
FLL Lock output
FLL Clock output
Table 69 GPIO Functions Available
IRQ/GPIO1
The IRQ/GPIO1 pin is configured using the register bits described in Table 70. By default, this pin is
IRQ output with pull-down resistor enabled.
REGISTER
Table 70 IRQ/GPIO1 Control
ADDRESS
IRQ/GPIO1
BCLK/GPIO4
BIT
3:0
5
4
GPIO1_SEL [3:0]
GPIO1_PU
GPIO1_PD
LABEL
IRQ / GPIO1
DEFAULT
0100
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
0
1
GPIO PINS
GPIO1 pull-up resistor enable
0 = pull-up disabled
1 = pull-up enabled
GPIO1 pull-down resistor enable
0 = pull-down disabled
1 = pull-down enabled
GPIO1 Function Select
0000 = Input pin
0001 = Clock output
(f=SYSCLK/OPCLKDIV)
0010 = Logic '0'
0011 = Logic '1'
0100 = IRQ (default)
0101 = FLL Lock
0110 = Mic Detect
0111 = Mic Short
1000 = DMIC clock out
1001 = FLL Clock Output
1010 to 1111 = Reserved
BCLK / GPIO4
PD, Rev 4.0, September 2010
DESCRIPTION
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Production Data
106