wm8350 Wolfson Microelectronics plc, wm8350 Datasheet - Page 183

• Manufacturer Part Number: wm8350
• Description: Wolfson Audioplus? Stereo Codec With Power Management
• Manufacturer: Wolfson Microelectronics plc

Production Data
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example, if the GPIO supply domain is DBVDD then the external pull-up voltage must be less than or
equal to DBVDD.
Note: Do not enable pull-up and pull-down resistors for the same GPIO pin.
Note: The internal pull-up and pull-down on GPIO10, GPIO11 and GPIO12 may be too weak for
many applications. If pull-up or pull-down is required on these pins, it is recommended to ensure that
the pull resistance is <100kΩ. This can be achieved using an external resistor on its own or in
combination with the internal resistance.
20.1.2
GPIO inputs have an optional de-bounce function to remove glitches from the input signal. This may
be useful when the GPIO is connected to a mechanical switch. The de-bounce function can be
enabled for each pin individually using GPn_DB, with a globally selectable de-bounce time set by
GP_DBTIME.
GPIO alternative functions PWR_ON, PWR_OFF and /WAKEUP are special cases with regard to
debouncing; these inputs have a debounce time of GP_DBTIME[1:0] + 40ms.
R128 (80h)
GPIO de-
bounce
R133 (85h)
GPIO Control
Note: n is a number between 0 and 12 that identifies the individual GPIO.
Table 121 Configuring GPIO De-bounce
20.1.3
The GPIO logic can raise a first-level interrupt, GPIO_INT (see Section 24). This interrupt is the
logical OR of the second-level GPIO interrupts described in Table 122.
R30 (1Eh)
GPIO Interrupt
Status
R38 (26h)
GPIO Interrupt
Mask
Note: n is a number between 0 and 12 that identifies the individual GPIO.
Table 122 GPIO Interrupts
ADDRESS
ADDRESS
INPUT DE-BOUNCE
GPIO INTERRUPTS
12:0
12:0
12:0
BIT
BIT
7:6
GPn_EINT [12:0]
“IM_” + name of respective bit
in R30
GPn_DB [12:0]
GP_DBTIME
[1:0]
LABEL
LABEL
DEFAULT
00
1
GPIOn interrupt.
(Trigger controlled by GPn registers.)
Note: This bit is cleared once read.
Mask bits for GPIO interrupts
Each of these bits masks the respective
bit in R30 when it is set to 1 (e.g.
GPn_EINT in R30 does not trigger a
GPIO_INT interrupt when IM_GPn_EINT
in R38 is set).
GPIOn debounce
0 = GPIO is not debounced.
1 = GPIO is debounced (time from
GP_DBTIME[1:0])
De-bounce time for all GPIO inputs
00 = 64μs
01 = 0.5ms
10 = 1ms
11 = 4ms
Note: PWR_ON, PWR_OFF and
/WAKEUP have additional debounce
times.
DESCRIPTION
DESCRIPTION
PD, June 2009, Rev 4.1
WM8350
183